Fluid composition sensor device and method of using the same

ABSTRACT

Various embodiments are directed to a fluid composition sensor device and method of using the same. In various embodiments, the fluid flow composition sensor is configured to receive a volume of fluid, the fluid composition sensor comprising a housing, a removable fluid flow component, an impactor nozzle, a collection media assembly dock element configured to receive a replaceable collection media assembly comprising a collection media configured to receive one or more particles within the volume of fluid, an imaging device configured to capture an image of at least a portion of the one or more particles received by the fluid composition sensor, and a controller configured to determine, based at least in part on the image, at least one particle characteristic of the volume of fluid. The imaging device may be configured to capture the image of one or more particles received by the fluid composition sensor using lensless holography.

BACKGROUND

Sensors and devices may be utilized to characterize various aspects offluids in a wide variety of applications. As just one example, sensordevices may be utilized for monitoring air conditions, such asmonitoring and characterizing the particulate content of a flow of air.However, existing fluid sensor devices provide limited functionality ingenerating data indicative of certain characteristics of fluids, such asthe unique identity and concentration of individual particles containedwithin a fluid flow. Fluid sensor devices can use holographic imagingmethods to characterize particle identity and concentration ofparticulate matter that has been collected via inertial impaction. It isdesirable to improve various aspects of particle sampling and analysis.In general, it can be advantageous for a fluid sampling device toutilize a sampling media that enables rapid and/or simplified sequentialsampling of particles. For devices utilizing holographic imaging (suchas lensless holography) for in situ particle analysis, it is desirableto avoid optical reflections and scattering in order to achieve optimalimage quality.

Accordingly, a need exists for an improved fluid sensor device capableof accurately collecting and analyzing the particle content of a samplevolume of fluid from an ambient environment using a single sensor devicein an easily repeatable manner.

BRIEF SUMMARY

Various embodiments described herein relate to apparatuses and methodsfor collecting and characterizing particles suspended within a fluid.Various embodiments are directed to a device for detecting fluidparticle characteristics comprising: a fluid composition sensorconfigured to receive a volume of fluid, the fluid composition sensorcomprising: a removable fluid flow component disposed within an internalsensor portion and configured to define at least a portion of a fluidflow path; a collection media assembly dock element configured toreceive a replaceable collection media assembly comprising a collectionmedia configured to receive one or more particles of a plurality ofparticles within the volume of fluid such that the replaceablecollection media assembly is arranged within the internal sensor portionin a particle collection position; an imaging device configured tocapture an image of at least a portion of the one or more particles ofthe plurality of particles received by the collection media; acontroller configured to determine, based at least in part on the image,at least one particle characteristic of the plurality of particles ofthe volume of fluid; wherein at least a portion of the fluid flow pathextends in a fluid flow direction that is at least substantially towardthe collection media; wherein the collection media assembly dock elementis configured to constrain relative movement between the replaceablecollection media assembly and the imaging device in a lateral direction.

In various embodiments, the imaging device may be configured to capturethe image of one or more particles of the plurality of particlesreceived by the collection media using lensless holography. In variousembodiments, the collection media assembly dock element may comprise oneor more alignment features configured to engage the replaceablecollection media assembly so as to constrain the replaceable collectionmedia assembly against movement relative to the collection mediaassembly dock element. In certain embodiments, the replaceablecollection media assembly may further comprise one or more alignmentfeatures configured to engage the collection media assembly dock elementso as to constrain the replaceable collection media assembly againstmovement relative to the collection media assembly dock element in atleast a second direction.

In various embodiments, the fluid composition sensor may furthercomprise a housing defining the internal sensor portion and comprising afluid inlet configured to receive the volume of fluid; wherein thehousing is selectively configurable between an open housingconfiguration and a closed housing configuration, wherein the openhousing configuration provides an opening through which a replaceablecollection media assembly may be removed from within the internal sensorportion, and wherein the fluid composition sensor in the closedconfiguration is configured to constrain the replaceable collectionmedia assembly against movement relative to the collection mediaassembly dock element in at least the lateral direction, a verticaldirection, and an angular direction. In certain embodiments, theremovable fluid flow component may be configured to be removable fromwithin the internal sensor portion when the fluid composition sensor inthe open configuration. Further, in certain embodiments, the removablefluid flow component may comprise a first fluid flow component part anda second fluid flow component part, wherein the first fluid flowcomponent part is configured to be separable from the second fluid flowcomponent to facilitate selective access to an internal portion of theremovable fluid flow component. In various embodiments, the fluidcomposition sensor may be configured such that when the fluidcomposition sensor is in the closed configuration, a verticalcompression force is applied to the replaceable collection mediaassembly so as to at least partially constrain the replaceablecollection media assembly in a vertical direction.

In various embodiments, the collection media assembly dock element maycomprise an imaging orifice configured so as to define a line of sightto the one or more particles received by the collection media, the lineof sight extending through at least a portion of the collection mediaassembly dock element. In certain embodiments, the fluid compositionsensor may further comprise a removable transparent protective coverarranged within the internal sensor portion and configured to cover atleast a portion of the imaging orifice. In various embodiments, theimaging device may be operatively secured to the collection mediaassembly dock element.

In various embodiments, the fluid flow path is defined at least in partby a fluid impaction outlet disposed within the internal sensor portionand configured relative to the collection media assembly dock element soas to direct the volume of fluid in a fluid flow direction at leastsubstantially perpendicular to the collection media of the replaceablecollection media assembly received by the collection media assembly dockelement. Further, in various embodiments, the fluid impaction outlet maybe defined at least in part by a fluid impaction outlet shape that is atleast substantially similar to a field of view shape of the imagingdevice. In certain embodiments, the fluid impaction outlet may bedefined at least in part by a fluid impaction outlet area that is atleast substantially similar to a field of view area of the imagingdevice disposed. In various embodiments, the fluid composition sensormay be configured such that at least a portion of the collection mediaof the replaceable collection media assembly received by the collectionmedia assembly dock element is at least substantially aligned with afield of view of the imaging device and a central axis of the fluidimpaction outlet. In various embodiments, the wherein the fluid flowpath may be defined at least in part by an impactor nozzle, and whereinthe fluid impaction outlet is defined by an impactor nozzle outlet ofthe impactor nozzle.

In various embodiments, the device may further comprise at least oneillumination source configured to emit one or more light beams so as toengage the collection media of the replaceable collection media assemblyreceived by the collection media assembly dock element and illuminatethe one or more particles received by the collection media. In variousembodiments, the fluid composition sensor may be configured such thatthe volume of fluid passes over at least a portion of an internalcircuitry disposed within the internal sensor portion before the volumeof fluid is dispensed from the internal sensor portion through a fluidoutlet of the fluid composition sensor. In various embodiments, one orboth of the controller and the imaging device may be configured to readone or more identification elements disposed on the replaceablecollection media assembly received by the collection media assembly dockelement so as to identify the replaceable collection media assembly,wherein the one or more identification elements configured to uniquelyidentify the replaceable collection media assembly. In certainembodiments, the fluid composition sensor may be configured toconsecutively receive a plurality of replaceable collection mediaassemblies within the internal sensor portion in series.

Various embodiments are directed to a method for detecting fluidparticle characteristics comprising: receiving, via a sensor, a volumeof fluid; directing the volume of fluid, via an impactor nozzle, towarda collection media of a replaceable collection media assembly;receiving, via the collection media, one or more particles of aplurality of particles within the volume of fluid; capturing, using animaging device disposed within the sensor, an image of the one or moreparticles of the plurality of particles received by the collectionmedia; determining, based at least in part on the image, at least oneparticle characteristic of the plurality of particles of volume offluid; and upon determining the at least one particle characteristic ofthe plurality of particles of volume of fluid, reconfiguring the sensorto an open configuration; and replacing the replaceable collection mediaassembly with a second replaceable collection media assembly; whereinthe second replaceable collection media assembly comprises at least onealignment feature, and wherein replacing the replaceable collectionmedia assembly with the second replaceable collection media assemblycomprises positioning the second replaceable collection media assemblywithin a portion of the sensor based at least in part on at least onealignment feature.

In various embodiments, the method may further comprise reconfiguringthe sensor to a closed configuration, wherein reconfiguring the sensorto the closed configuration comprises constraining the secondreplaceable collection media assembly in at least a lateral direction, avertical direction, and an angular direction relative to the sensor. Incertain embodiments, the image of the one or more particles of theplurality of particles received by the collection media may be capturedusing lensless holography.

Various embodiments are directed to a collection media assembly forreceiving one or more particles from a volume of fluid within a fluidcomposition sensor, the collection media assembly comprising: a housing;a transparent substrate; a collection media disposed upon thetransparent substrate and configured to receive one or more particlesfrom a volume of fluid received through a fluid inlet; and at least onealignment feature; wherein the housing defines an open lower endconfigured for interaction with an imaging device, such that the one ormore particles received by the collection media are visible through thetransparent substrate from the open lower end of the housing; andwherein each of the at least one alignment features is configured toengage a corresponding element disposed within the fluid compositionsensor so as to constrain relative movement between the collection mediaassembly and the corresponding element in at least a first direction.

In various embodiments, the collection media assembly may furthercomprise at least one orifice extending through at least a portion ofthe housing, the at least one orifice being arranged so as to define aline of sight to the one or more particles received by the collectionmedia, the line of sight extending through at least a portion of thehousing. In certain embodiments, the at least one orifice may beconfigured to enable the volume of fluid to flow through the collectionmedia assembly. In various embodiments, the housing may comprise a firsthousing portion and a second housing portion, wherein the first housingportion and the second housing portion are configured to at leastpartially constrain the collection media relative to the housing. Invarious embodiments, the housing may be defined at least in part by acentral vertical axis extending therethrough in a vertical direction,and wherein the housing comprises a perimeter that is asymmetric aboutthe central vertical axis.

In various embodiments, the at least one alignment features of thecollection media assembly may be configured to constrain relativemovement between the collection media assembly and an imaging devicedisposed within the fluid composition sensor. In certain embodiments,the at least one alignment features of the collection media assembly maybe configured to constrain the replaceable collection media assemblyrelative to the fluid composition sensor in at least a lateraldirection, a vertical direction, and an angular direction. In variousembodiments, the fluid inlet may be defined at least in part by a fluidinlet shape that is at least substantially similar to a field of viewshape of an imaging device disposed within the fluid composition sensor.

In various embodiments, the fluid inlet may be defined at least in partby a fluid inlet area that is at least substantially similar to a fieldof view area of an imaging device disposed within the fluid compositionsensor. In certain embodiments, the collection media assembly mayfurther comprise an impactor nozzle configured to define at least aportion of the fluid inlet of the collection media assembly, wherein theimpactor nozzle is configured to direct the volume of fluid toward thecollection media in a fluid flow direction that is at leastsubstantially perpendicular to the collection media. In certainembodiments, the impactor nozzle may comprise an impactor nozzle outletdefined at least in part by a nozzle outlet shape that is at leastsubstantially similar to a field of view shape of the imaging devicedisposed within the fluid composition sensor. In certain embodiments,the impactor nozzle may comprise an impactor nozzle outlet defined atleast in part by a nozzle outlet area that is at least substantiallysimilar to a field of view area of the imaging device disposed withinthe fluid composition sensor.

Various embodiments are directed to a device for detecting fluidparticle characteristics comprising: a fluid composition sensorconfigured to receive a volume of fluid, the fluid composition sensorcomprising: a housing defining an internal sensor portion and comprisinga fluid inlet configured to receive the volume of fluid; a fluid flowcomponent disposed within the internal sensor portion and configured todefine at least a portion of a fluid flow path; an impactor nozzleconfigured to receive at least a portion of the volume of fluid suchthat the at least a portion of the volume of fluid received by theimpactor nozzle is directed in a fluid flow direction; at least onecollection media assembly dock element configured to receive areplaceable collection media assembly comprising a collection mediaconfigured to receive one or more particles of a plurality of particleswithin the volume of fluid such that the replaceable collection mediaassembly is arranged within the internal sensor portion in a particlecollection position and constrained against movement relative to the atleast one collection media assembly dock element in at least onedirection; an imaging device configured to capture an image of at leasta portion of the one or more particles of the plurality of particlesreceived by the collection media of the replaceable collection mediaassembly received by the at least one collection media assembly dockelement; a collection media assembly ejection element; and a controllerconfigured to determine, based at least in part on the image, at leastone particle characteristic of the plurality of particles of volume offluid; wherein the fluid flow direction is at least substantially towardthe collection media; wherein the fluid composition sensor is configuredto receive a pressing force from the replaceable collection mediaassembly so as to constrain the replaceable collection media assemblyagainst movement relative to the imaging device in at least a verticaldirection.

In various embodiments, the fluid composition sensor may be configuredto, upon receiving the pressing force received from the replaceablecollection media assembly, align the replaceable collection mediaassembly in a position at least substantially adjacent the imagingdevice so as to define an air seal that at least partially isolates theimaging device from the volume of fluid. In various embodiments, one orboth of the controller and the imaging device may be configured to readone or more identification elements disposed on the replaceablecollection media assembly received by the collection media assembly dockelement so as to identify the replaceable collection media assembly, andwherein the one or more identification elements are configured touniquely identify the replaceable collection media assembly. In variousembodiments, the impactor nozzle may comprise an impactor nozzle outletdefined at least in part by a nozzle outlet shape that is at leastsubstantially similar to a field of view shape of the imaging device. Incertain embodiments, the impactor nozzle may comprise an impactor nozzleoutlet defined at least in part by a nozzle outlet area that is at leastsubstantially similar to the field of view area of the imaging device.In various embodiments, the collection media assembly ejection elementmay be configured to engage a latch of the replaceable collection mediaassembly received by the at least one collection media assembly dockelement, the latch being configured to impede the removal of thereplaceable collection media assembly from the sensor.

Various embodiments are directed to a collection media assembly forreceiving one or more particles from a volume of fluid within a fluidcomposition sensor, the collection media assembly comprising: a frameelement; a transparent substrate; a collection media disposed upon thetransparent substrate and configured to receive one or more particlesfrom a volume of fluid; and at least one compression element configuredto apply a pressing force against an adjacent portion of an internalsensor portion within the fluid composition sensor so as to constrainthe replaceable collection media assembly relative to an imaging deviceof the fluid composition sensor in at least one direction; and a latchconfigured to impede the removal of the replaceable collection mediaassembly from the sensor; wherein each of the at least one alignmentfeatures is configured to engage a corresponding element disposed withina fluid composition sensor so as to constrain relative movement betweenthe collection media assembly and the corresponding element in at leasta vertical direction. In various embodiments, the collection mediaassembly may further comprise one or more identification elementsconfigured to uniquely identify the replaceable collection mediaassembly, wherein the one or more identification elements are furtherconfigured to be read by the imaging device.

Various embodiments are directed to a method for detecting fluidparticle characteristics comprising: inserting at least a portion of acollection media assembly into an interior portion of a sensor, thecollection media assembly comprising: a collection media configured toreceive one or more particles of a plurality of particles within thevolume of fluid; at least one compression element configured to apply apressing force against an adjacent portion of the internal sensorportion so as to constrain the replaceable collection media assemblyrelative to the imaging device in at least one direction; a latchconfigured to impede the removal of the replaceable collection mediaassembly from the sensor; receiving, via the sensor, a volume of fluid;directing the volume of fluid, via an impactor nozzle in a first nozzleconfiguration, toward the collection media of the collection mediaassembly, receiving, via the collection media, one or more particles ofa plurality of particles within the volume of fluid; capturing, using animaging device disposed within the sensor, an image of the one or moreparticles of the plurality of particles received by the collectionmedia; determining, based at least in part on the image, at least oneparticle characteristic of the plurality of particles of volume offluid; and upon determining the at least one particle characteristic ofthe plurality of particles of volume of fluid, removing the collectionmedia assembly from the internal portion of the sensor. In certainembodiments, method may further comprise identifying, using one or bothof a sensor controller and the imaging device, the replaceablecollection media assembly based at least in part on an identifyingelement disposed thereon.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the accompanying drawings, which are notnecessarily drawn to scale, and wherein:

FIG. 1 illustrates a perspective view of an exemplary fluid compositionsensor in accordance with various embodiments.

FIG. 2 illustrates a cross-sectional view of an exemplary apparatus inaccordance with one embodiment described herein.

FIG. 3 illustrates a cross-sectional view of an exemplary apparatus inaccordance with one embodiment described herein

FIG. 4 illustrates an exploded view of an exemplary apparatus inaccordance with various embodiments described herein.

FIG. 5 illustrates a perspective view of an exemplary fluid compositionsensor in accordance with various embodiments.

FIGS. 6A-6B illustrate perspective views of an exemplary apparatus inaccordance with various embodiments.

FIG. 7 illustrates an exploded view of an exemplary apparatus inaccordance with various embodiments described herein.

FIG. 8 illustrates a perspective view of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein.

FIG. 9 illustrates an exploded view of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein.

FIGS. 10A-10B illustrate perspective views of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein.

FIGS. 11A-11B illustrate perspective views of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein.

FIGS. 12A-12B illustrate perspective views of exemplary replaceablecollection media assemblies in accordance with various embodimentsdescribed herein.

FIG. 13 illustrates a perspective view of an exemplary collection mediaassembly dock element in accordance with various embodiments describedherein.

FIGS. 14A-14B illustrate cross-sectional views of an exemplary apparatusin accordance with one embodiment described herein.

FIGS. 15A-15B illustrate cross-sectional views of an exemplary apparatusin accordance with one embodiment described herein.

FIG. 16 illustrates a perspective view of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein.

FIG. 17 illustrates a cross-sectional view of an exemplary apparatus inaccordance with one embodiment described herein.

FIG. 18 schematically illustrates an exemplary apparatus forimplementing various embodiments of the present disclosure.

DETAILED DESCRIPTION

The present disclosure more fully describes various embodiments withreference to the accompanying drawings. It should be understood thatsome, but not all embodiments are shown and described herein. Indeed,the embodiments may take many different forms, and accordingly thisdisclosure should not be construed as limited to the embodiments setforth herein. Rather, these embodiments are provided so that thisdisclosure will satisfy applicable legal requirements. Like numbersrefer to like elements throughout.

It should be understood at the outset that although illustrativeimplementations of one or more aspects are illustrated below, thedisclosed assemblies, systems, and methods may be implemented using anynumber of techniques, whether currently known or not yet in existence.The disclosure should in no way be limited to the illustrativeimplementations, drawings, and techniques illustrated below, but may bemodified within the scope of the appended claims along with their fullscope of equivalents. While values for dimensions of various elementsare disclosed, the drawings may not be to scale.

The words “example,” or “exemplary,” when used herein, are intended tomean “serving as an example, instance, or illustration.” Anyimplementation described herein as an “example” or “exemplaryembodiment” is not necessarily preferred or advantageous over otherimplementations. As used herein, a “fluid” may be embodied as a gas, aliquid, or a combination of a gas and a liquid in a single flow. Thus,the term “fluid” encompasses various materials subject to flow, such as,but not limited to, liquids and/or gases (e.g., air, oil, or the like).Thus, various embodiments are directed to fluid sensing systems, such asgas sensing systems (e.g., certain embodiments being specificallyconfigured for operation with air; other embodiments being configuredfor operation with other gases, such as inert gases, volatile gases,and/or the like), liquid sensing systems, and/or the like.

Overview

Described herein is a device (which may be referred to as a fluidcomposition sensor, a fluid particulate sensor, a gas particulatesensor, or an air particulate senor as discussed herein) configured tocharacterize and monitor particulate matter within a volume of fluid.The device discussed herein may be configured to quantify and classifythe particles within a volume of fluid based at least in part on theimaging of particles received by a collection media of a fluidcomposition sensor. Further, the device discussed herein may beconfigured to characterize the particle composition within the volume offluid by directly identifying the particle size and particle type ofeach of the particles received by the collection media of the fluidcomposition sensor. By directly determining the particle size andparticle type, the device as described herein may be configured todetect a change in particle composition within a volume of fluid overtime and/or location.

Further, the device described herein may be configured to execute both aparticle collection function and a particle analysis function withoutrequiring the time, effort, and inherent inaccuracies associated withremoving a collection media from a sensor device and transporting themedia to a secondary location for subsequent analysis. The devicedescribed herein facilitates both a particle collection function and aparticle analysis function by enabling an imaging device disposed withinthe fluid composition sensor to capture an image of a plurality ofparticles received by the collection media while the replaceablecollection media assembly remains secured in a particle collectionposition within an internal portion of the sensor.

Further, the device described herein may be configured to increasedevice reliability and user satisfaction associated with the device byutilizing one or more replaceable components. In accordance with certainembodiments discussed herein, one or more components of the device maybe easily removed from an internal portion of the device facilitate thecleaning and/or replacement thereof, thereby minimize the risk ofcontamination of samples and/or system inaccuracies caused by imagedistortion generated by accumulated particulate matter disposed withinthe device. In accordance with certain embodiments discussed herein, thecollection media used to collect particles from a volume of fluid withinthe fluid composition sensor may be either manually or automaticallyreplaceable (within a fluid collection position) upon of a samplecollection process. The fluid composition sensor and the replaceablecollection media assembly include alignment features andself-positioning elements that facilitate the repeatability of insertinga collection media into a device in an arrangement that enables theoperability of both a particle collection functionality and a particleanalysis functionality of the sensor. The device herein may minimizeintermittent user-interaction with the collection media, therebyexpediting a sample collection process, reducing the physical workrequired of a user, facilitating measurement automation, and minimizingdevice failures caused by misalignment during a user-definedreconfiguration of one or more device components.

Fluid Composition Sensor

The fluid composition sensor 10 may be configured to receive a volume offluid flowing therethrough. Specifically, the fluid composition sensor10 may be configured to receive a volume of a gas, such as air, flowingtherethrough. In various embodiments, the fluid composition sensor 10may be further configured to capture an image of one or more particlesof a plurality of particles present within the received volume of fluid.As illustrated in FIG. 1, the fluid composition sensor 10 may comprise ahousing 11 defining an internal sensor portion in which one or morecomponents of an exemplary fluid composition sensor 10 described hereinmay be at least partially disposed. In various embodiments, the housingmay comprise rigid materials (e.g., rigid plastic materials) and/orresilient materials (e.g., resilient polymeric materials formingprotective sleeves on an upper and lower end of the housing). In variousembodiments, the housing 11 may comprise an upper surface and bottomsurface, with one or more sidewalls extending therebetween in asubstantially vertical direction. As described herein, the one or moresidewalls of the fluid composition sensor housing 11 may define at leasta portion of the height of the fluid composition sensor 10, wherein theheight of the sensor 10 extending in the z-direction. Similarly, thebottom surface of the fluid composition sensor housing 11 may extendalong an at least substantially horizontal plane defining at least aportion of both the length and the width of the fluid composition sensor10, wherein the length and the width of the sensor 10 extending in thex-direction and the y-direction, respectively. The housing 11 of thefluid composition sensor 10 may comprise a sensor fluid inlet 18embodied as an opening through which the fluid composition sensor mayreceive a volume of fluid from an ambient environment. As describedherein, the fluid composition sensor 10 may comprise a power supply(e.g., batteries 80 discussed herein) and a controller 50 such that oneor more components of the fluid composition sensor 10, as describedherein, may be electronically and communicatively connected to thecontroller 50.

In various embodiments, as illustrated in FIGS. 2 and 3, a fluidcomposition sensor 10 may comprise an illumination source 60, acontroller 50, a replaceable collection media assembly 100, a collectionmedia assembly dock element 200, and an imaging device 300. Further, invarious embodiments, the fluid composition sensor 10 may furthercomprise a removable fluid flow component 40 configured to define afluid flow path and direction within the fluid composition sensor 10from a sensor fluid inlet 18 in a direction at least substantiallytoward a collection media disposed within sensor 10. The fluidcomposition sensor 10 of the illustrated embodiment further comprises afan or pump 70 configured to pull the volume of fluid into and throughthe fluid composition sensor 10 along the defined fluid flow path, apower source 80 configured to power the fluid composition sensor, and/orinternal circuitry 18 configured to be in electronic communication withone or more of the aforementioned components of the fluid compositionsensor 10. In various embodiments, the fan or pump 70 is calibrated,such that the flow rate of fluid moving through the device isknown/determined based at least in part on the operating characteristics(e.g., operating power) of the fan or pump 70. In various embodiments,the fluid composition sensor may further comprise one or more buttons(or other user interface elements) disposed about the housing 11, eachof which may be in electronic communication with the internal circuitry18 of the sensor 10 to, upon user engagement with the button, facilitateone or more sensor functionalities as described herein. For example,user engagement with a button may initiate the transmission to acontroller 50 of at least one electrical signal associated with the oneor more sensor functionalities corresponding to the button.

In various embodiments, as described herein, the fluid compositionsensor 10 may be configured to execute both a particle collectionfunction and a particle analysis function. FIG. 2 illustrates aperspective sectional view of an exemplary fluid composition sensor 10according to various embodiments described herein. In particular, theexemplary fluid composition sensor 10 illustrated in FIG. 2 is shown asexecuting at least a portion of the particle collection function of thesensor 10. As described herein, the particle collection function of thefluid composition sensor 10 may correspond to the fluid compositionsensor 10 receiving from an ambient environment a volume of fluidcomprising a plurality of particles and utilizing a removable fluid flowcomponent 40 and an impactor nozzle 112 disposed within the internalsensor portion 13 to direct the volume of fluid toward a collectionmedia 131 disposed within sensor 10. As described herein, the removablefluid flow component 40 may be configured to receive the volume of fluidfrom the sensor fluid inlet 18 through at least one fluid flow componentinlet 41A and may define a fluid flow path 90 such that the volume offluid may travel from the fluid flow component inlet 41A to the impactornozzle 112. The impactor nozzle 112 may comprise a nozzle inletconfigured to receive the volume of fluid from the removable fluid flowcomponent 40 and a nozzle outlet, wherein the nozzle inlet comprises across-sectional area that is larger than that of the nozzle outlet. Theimpactor nozzle 112 may be configured such that the volume of fluidcontaining the plurality of particles passes therethrough in a fluidflow direction at least substantially perpendicular to the collectionmedia 131. As described, the variable cross-sectional areas of theimpactor nozzle 112 may be configured to increase the velocity of thevolume of fluid flowing through the nozzle 112 (e.g., the plurality ofparticles therein) and induce laminar flow such that at least a portionof the particles of the plurality of particles within the volume offluid comprise a momentum sufficient to impact the collection media 131and become disposed therein. For example, the volume of fluid may travelfrom the outlet of the impactor nozzle 112 and pass across at least aportion of a surface of the collection media 131 such that at least aportion of the plurality of particles within the volume of fluid becomedisposed within the collection media 131.

In various embodiments, upon passing across the surface of thecollection media 131, the volume of fluid may continue to travel withinan internal sensor portion 13 along a fluid flow path 90. At least aportion of the volume of fluid may be directed (e.g., by the fan and/orpump 70) to an outlet of the fluid composition sensor 10 (e.g., one ormore exhaust slots) whereby the volume of fluid may be dispensed backinto the ambient environment. In various embodiments, the fluidcomposition sensor 10 may be configured such that prior to beingdispensed from the sensor 10, at least a portion of the volume of fluidmay be directed toward the internal circuitry 18 within the internalsensor portion 13 and circulated so as to facilitate the cooling of theinternal circuitry 18 by passing the volume of fluid over at least aportion thereof. In such a circumstance, the fluid composition sensor 10may be configured such that the portion of the volume of fluid used tocool the internal circuitry 18 may be subsequently dispensed from theoutlet of the sensor 10.

FIG. 3 illustrates a cross-sectional view of an exemplary fluidcomposition sensor 10 according to various embodiments described herein.In particular, the exemplary fluid composition sensor 10 illustrated inFIG. 3 is shown as executing at least a portion of the particle analysisfunction of the sensor 10. As described herein, the particle analysisfunction of the fluid composition sensor 10 may correspond to the fluidcomposition sensor 10 capturing an image of the one or more particlesreceived by—and disposed within—the collection media 131 anddetermining, based at least in part on the captured image, at least oneparticle characteristic of the volume of fluid received by the fluidcomposition sensor 10. In various embodiments, the fluid compositionsensor 10 may comprise an illumination source 60 configured to emit oneor more light beams. In various embodiments, the illumination source 60may be a laser, lamp, light-emitting diode (LED), and/or the like, whichmay be collectively configured to generate a light beam (e.g.,ultraviolet, visible, infrared, white, a single visible color, ormultiple color light) that may be emitted toward the collection media131, as described herein in further detail. For example, an illuminationsource 60 of the fluid composition sensor 10 may be configured to emitone or more light beams 61 so as to engage the collection media 131 andilluminate the one or more particles disposed therein, as describedherein. In various embodiments, as illustrated in FIG. 3, the fluidcomposition sensor 10 may be configured such that the illuminationsource 60 is at least substantially aligned with the imaging device 300.Further, for example, the illumination source 60 may be at leastsubstantially aligned with the central axis of the impactor nozzle 112.In such a configuration, the illumination source 60 may be arranged suchthat the light beam 61 emitted therefrom extends through the removablefluid flow component 40 in a direction that is at least substantiallyaligned with the central nozzle axis, such that at least a portion ofthe one or more light beams 61 extend through both the nozzle inlet andthe nozzle outlet of the impactor nozzle 112 to illuminate the one ormore particles disposed in the collection media 131. As describedherein, an imaging device 300 disposed within the internal sensorportion 13 may be configured to utilize the light beam 61 emitted fromthe illumination source 60 in order to capture an image of the one ormore particles of the plurality of particles received by the collectionmedia 131 using one or more imaging techniques such as, for exampleholographic microscopy (e.g., lensless holography) and/or the like.

The fluid composition sensor 10 (e.g., controller 50) may be configuredto analyze the captured image, as described herein, so as to determine aparticle size and/or other particle characteristics of one or more ofthe particles captured within the collection media 131. For example,wherein the imaging device 300 is configured to utilize lenslessholography analyze one or more particles embedded within the collectionmedia 131, the imaging device 300 may computationally produce an imageof the one or more particles received by the collection media 131 bydigitally reconstructing one or more microscopic images of one or moreparticles without using a lens. In executing the particle analysisfunction as described herein, the fluid composition sensor 10 maycharacterize the particle composition within the volume of fluid bydirectly identifying the particle size and/or particle type of each ofthe particles received by the collection media 131. For example, thefluid composition sensor may detect a change in particle compositionwithin a volume of fluid over time and/or location.

As described herein, in various embodiments, the particle collectionfunction and the particle analysis function of the fluid compositionsensor 10 may be executed in sequence, such that upon determining thatan entirety of a sample volume of fluid has passed across a surface of acollection media 131, and thus, that the need for the particlecollection functionality of the fluid composition sensor has been atleast temporarily exhausted, the fluid composition sensor may beconfigured to initiate the particle analysis functionality.

As described above, in various embodiments, the fluid composition sensor10 may comprise a lens free microscope, such as one described in WIPOPublication Number 518/165590, which is incorporated herein by referencein its entirety. In various embodiments, a lens-free microscope mayutilize one or more techniques, such as, for example, holographicmicroscopy (e.g., lensless holography), to capture a particle image, asdescribed herein, of the one or more particles of a plurality ofparticles received by a collection media 131. Alternatively, the fluidcomposition sensor 10 may comprise a lens-based imaging device or anyother apparatus configured to capture an image which may be analyzed, asdescribed herein, so as to determine a particle size or other particlecharacteristics of one or more particles captured from within a volumeof fluid by a collection media 131 disposed within the internal sensorportion of the fluid composition sensor 10. In various embodiments, alens-based imaging device may utilize one or more imaging techniques,such as, for example, optical microscopy, to capture a particle image,as described herein, of the one or more particles of a plurality ofparticles received by a collection media 131, as described herein.

In various embodiments, the fluid composition sensor 10 may be connectedto a power supply 80 configured to receive power and power the fluidcomposition sensor 10. As non-limiting examples, the power supply 80 maycomprise one or more batteries, one or more capacitors, one or moreconstant power supplies (e.g., a wall-outlet), and/or the like. In someembodiments the power supply 80 may comprise an external power supplypositioned outside of the fluid composition sensor 10 and configured todeliver alternating or direct current power to the fluid compositionsensor 10. Further, in some embodiments, as illustrated in FIGS. 2 and3, the power supply 80 may comprise an internal power supply, forexample, one or more batteries, positioned within the housing 11 of thefluid composition sensor 10. In various embodiments, a power supply 80may be connected to the controller 50 to enable distribution of powerthrough the controller to the fluid composition sensor 10.

As described, the imaging device 300 of the fluid composition sensor 10may be positioned at least substantially adjacent (e.g., in contact withor spaced a distance away from) the collection media 131 such that theimaging device 300 may effectively capture one or more images of the oneor particles embedded within the collection media 131. As discussedherein, the collection media 131 may be replaceable (e.g., as a part ofa cassette that may be inserted into and/or removed from the fluidcomposition sensor 10), and accordingly the fluid composition sensor 10may define one or more alignment features, support features, and/or thelike for maintaining a desired positioning of the collection media 131relative to the imaging device 300 (e.g., such that a bottom surface ofthe collection media 131 is in contact with or proximate (e.g., within 5mm, within 3 mm, within 1 mm and/or the like) an imaging surface of theimaging device 300. Such alignment features and/or support features maycomprise one or more grooves, slots, ridges, and/or the like configuredto position the collection media 131 in a desired position relative tothe imaging device 300. In various embodiments, the fluid compositionsensor 10 (e.g., the imaging device 300) may have a designated field ofview for capturing, permanently and/or temporarily, an image of multipleparticles of the plurality of particles simultaneously. The collectionmedia 131 may be positioned within the fluid composition sensor 10relative to the imaging device 300 such that at least a portion of thecollection media 131 is within the field of view of the imaging device300. Further, the collection media 131 may be positioned relative to theimaging device 300 such that the portion (e.g., at least a portion) ofthe collection media 131 within which the particles from the volume offluid flowing through the sensor 10 are disposed is visible by theimaging device 300 (i.e. within the field of view). In variousembodiments, the field of view of the imaging device 300 may berectangular and may be configured to comprise an aspect ratio of up to1:20. The aspect ratio may be selectively configured to optimize thefield of view of the imaging device 300 based at least in part on afluid flow velocity, pressure drop, and/or Reynolds number associatedwith a volume of fluid traveling along at least a portion of the fluidflow path (e.g., through an impactor nozzle 112), each of which may beoptimized in order to maximize flow performance and particle collection.For example, in various embodiments, the field of view of the imagingdevice 300 may have an aspect ratio of 3:4.

However, it should be understood that other shapes, sizes, andproportions of a field of view may be provided in other embodiments(e.g., round, ovular, rectangular with a different aspect ratio, and/orthe like).

As described herein, the field of view of the imaging device 300 on thecollection media 131 may correspond to the configuration of the imagingdevice 300 relative to the collection media 131. In particular, thefield of view of the imaging device 300 may be defined at least in partby the distance between the imaging device 300 and the collection media131 disposed within the sensor 10. Further, as described herein, thearea of the collection media 131 that receives particles from anexemplary volume of fluid as the exemplary fluid flows through thesensor 10 may correspond to the configuration of the outlet of theimpactor nozzle 112 from which the exemplary volume of fluid isdispensed prior to impacting the collection media 131. For example, thearea of the collection media 131 that receives particles from a volumeof fluid may be defined at least in part by the shape of the outlet ofthe impactor nozzle 112 and the distance between the nozzle outlet andthe collection media 131. Accordingly, the outlet of the impactor nozzle112 may be configured so as to comprise a shape that corresponds withthe shape of the field of view of the imaging device 300 of the sensor10. Specifically, the outlet of the impactor nozzle 112 may beconfigured so as to define a shape that is at least substantiallysimilar to the size and shape of the field of view of the imaging device300 of the sensor 10. As described herein, in various embodiments, thefield of view of the imaging device 300 may have an aspect ratio of upto 1:20, so as to optimize the field of view based at least in part onone or more fluid flow characteristics of the volume of fluid. Forexample, in an exemplary circumstance wherein the field of view isdefined by an aspect ratio of 3:4 having a defined size, the outlet ofthe impactor nozzle 112 may comprise a rectangular cross-section with alength-to-width ratio of 3:4 and having the same defined size (e.g.,shape and/or area), corresponding to the configuration of the imagingdevice 300. For example, the impactor nozzle 112 may comprise arectangular cross-section with a length of at least substantiallybetween 1 mm and 10 mm (between 3 mm and 3.6 mm) and a width of at leastsubstantially between 1 mm and 10 mm (between 3.9 mm and 4.5 mm).

Further, in various embodiments, the fluid composition sensor 10 may beconfigured such that a central axis of the impactor nozzle 112 is atleast substantially aligned with the field of view of the imaging device300 in order to facilitate the convergence of the field of view of theimaging device 300 and the portion of the collection media 131configured to receive particles from the volume of fluid flowing throughthe sensor 10. As described herein, in order to ensure proper alignmentof each of the aforementioned components, the fluid composition sensor10 may be configured to secure the collection media 131, the impactornozzle 112, and the imaging device 300 within the sensor (e.g.,temporarily during the execution of the particle collection and/orparticle analysis functions) in each of the x-direction, they-direction, the z-direction, and the angular direction. For example,the fluid composition sensor 10 may be configured such that thecollection media 131 is arranged therein at a predetermined distanceaway from both the imaging device 300 and the outlet of the impactornozzle 112, respectively, wherein both the distance between thecollection media 131 and the imaging device 300 and the distance betweenthe collection media 131 and the and the outlet of the impactor nozzle112 are calibrated to optimize the particle collection and particleanalysis functions of sensor 10, as described herein.

As described herein, in various embodiments, a fluid composition sensormay be configurable between an open housing configuration and a closedconfiguration. In various embodiments, the open housing configuration ofa fluid composition sensor 10 may facilitate the removal of one or moresensor components from within the internal sensor portion 13. Forexample, a fluid composition sensor 10 in an open housing configurationmay be configured so as to allow for the reconfiguration of a collectionmedia assembly 100 relative to at least a portion of the internal sensorportion 13 of the housing 11. In various embodiments wherein the fluidcomposition sensor 10 is in an open configuration, a collection mediaassembly 100 comprising a collection media 131 disposed therein may beremoved from a particle collection position within the internal sensorportion 13 of the fluid composition sensor 10. For example, upondetermining that at least substantially the entirety of a sample volumeof fluid has passed across a surface of the collection media 131 andthat the one or more images of the particles needed to enable theparticle analysis function of the sensor 10 have been captured, thecollection media assembly 100 may be removed from the internal sensorportion 13 and transported to an exemplary secondary location. While thefluid composition sensor 10 is in an open configuration, the removedcollection media assembly 100 may be replaced with a different, unusedreplaceable collection media assembly 100.

As a further example, in various embodiments, the open sensorconfiguration of a fluid composition sensor 10 may facilitate theremoval of the removable fluid flow component 40 from the internalsensor portion 13 of the housing 11. As described herein, the removablefluid flow component 40 may be configured to receive the volume of fluidfrom the sensor fluid inlet 18 through at least one fluid flow componentinlet 41A and may define a fluid flow path 90 such that the volume offluid may travel from the fluid flow component inlet 41A to an impactornozzle 112. The removable fluid flow component 40 may define an interiorportion through which each sample volume of fluid (and each of theplurality of particles therein) received by the sensor 10 passes, suchthat, after one or more uses, an undesirable volume of particulatematter may begin to accumulate within the interior portion of theremovable fluid flow component 40. The removable fluid flow component 40may be arranged such that, when the sensor 10 is in an openconfiguration, the fluid flow component 40 may be removed from theinternal sensor portion 13 of the fluid composition sensor 10 tofacilitate the cleaning and/or replacement of the fluid flow component40 so as to decrease the amount of undesired particulate present thereinand minimize the risk of system error caused by contamination.

FIG. 4 illustrates a perspective view of an exemplary fluid compositionsensor 10 in an open configuration according to an embodiment describedherein. In particular, FIG. 4 illustrates an exemplary fluid compositionsensor 10 defining an open sensor configuration, wherein the fluidcomposition sensor 10 comprises an upper sensor housing 20 and a lowersensor housing 30 that are connected to one another via a hingedconnection 16 such that the sensor 10 may be opened by moving the uppersensor housing 20 about the hinged connector 16 relative to the lowersensor housing 30. In the illustrated embodiment, the hinges are hiddenhinges (e.g., barrel hinges) that are entirely contained within theperimeter of the housing and which enable a flush connection betweenplanar surfaces of the upper sensor housing 20 and the lower sensorhousing 30 when in the closed position. However, it should be understoodthat other hinging configurations may be provided in other embodiments.Moreover, although not shown, it should be understood that the hingeconfiguration may additionally comprise one or more electricalconnectors, electrical connections, and/or the like, thereby enablingthe transmission of electrical power and/or control signals between thelower sensor housing 30 and the upper sensor housing 20. As illustrated,the upper sensor housing 20 and the lower sensor housing 30 areconfigured such that when the exemplary fluid composition sensor 10 isin a closed configuration, the interface between the two sensor housingportions 20, 30 defines an at least substantially horizontal plane. Invarious embodiments, the fluid composition sensor may comprise a latchmechanism 17 configured to secure the upper sensor housing 20 inposition relative to the lower sensor housing 30 such that the sensor 10is locked in the closed configuration. The latch mechanism 17 may beconfigured to disengage based at least in part on detecting userinteraction therewith (e.g., via a button disposed about the sensorhousing 11 that is mechanically connected to the latch 17) toselectively reconfigure the fluid composition sensor 10 from the closedconfiguration to an open configuration, as described herein. Althoughillustrated as a mechanical latch mechanism, it should be understoodthat the latch mechanism 17 may be embodied as any means configured tosecure the upper sensor housing 20 to a lower sensor housing 30 so as toprevent the relative movement therebetween.

In various embodiments, the upper sensor housing 20 defines an internalsensor portion 13 configured to receive the removable fluid flowcomponent 40. The upper sensor housing 20 may be configured to restrictthe lateral movement of the removable fluid flow component 40 disposedtherein relative to the internal sensor portion 13, wherein the lateralmovement of the fluid flow component 40 is movement in a direction thatis at least substantially perpendicular to a removal/insertion directionof the fluid flow component 40 (i.e. the direction in which theremovable fluid flow component 40 is removed from and/or inserted intothe upper sensor housing 20). For example, one or more portions of theupper sensor housing 20 may engage the removable fluid flow component 40so as to stabilize the position of the fluid flow component 40 relativeto the sidewalls of the internal sensor portion 13 of the upper sensorhousing 20, such that when the fluid composition sensor 10 is in aclosed configuration, the fluid flow component 40 is restricted frommoving in the x-y plane. Further, in various embodiments, the internalsensor portion 13 of the upper sensor housing 20 may comprise a geometrycorresponding to an asymmetric external geometry of the removable fluidflow component 40 such that the fluid flow component 40 will only fitinto the upper sensor housing 20 when inserted into the internal sensorportion 13 in an angular configuration that ensures proper alignment ofthe fluid flow component 40 relative to, for example, an illuminationsource, an impactor nozzle, a collection media assembly and/or animaging device positioned within the housing 11 of the sensor 10.

Additionally, the fluid composition sensor 10 may be configured suchthat when the sensor 10 is in a closed configuration, the upper sensorhousing 20 may restrict the vertical movement of the removable fluidflow component 40 disposed therein relative to the internal sensorportion 13, wherein the vertical movement of the fluid flow component 40is movement in a direction that is at least substantially similar to theremoval/insertion direction thereof. For example, in various embodimentswherein the impactor nozzle of the fluid flow sensor 10 is not attachedto the removable fluid flow component 40 (e.g., wherein the impactornozzle defines an inlet portion of a collection media assembly 100;wherein the impactor nozzle defines a portion of the housing 11 of thesensor 10), one or more portions of the upper sensor housing 20 mayengage the removable fluid flow component 40 so as to apply acompression force onto the fluid flow component in the z-direction so asto stabilize the position of the fluid flow component 40 relative to theimpactor nozzle and/or the collection media. In such a configuration,when the fluid composition sensor 10 is in a closed configuration, thefluid flow component 40 may be restricted from moving in the z-directionrelative to the collection media 131. In addition to further stabilizingthe position of the removable fluid flow component 40 relative to thecollection media 131, the vertical compression force applied to thefluid flow component 40 from the upper sensor housing 20 may function tocreate a secured seal at the outlet of the fluid flow component 40 so asto isolate the sample volume of fluid flowing through fluid flowcomponent 40 from a volume of ambient fluid.

In various embodiments, as shown in the exemplary embodiment illustratedin FIG. 4, the lower sensor housing 30 of the fluid composition sensor10 may comprise a collection media assembly dock element 200 configuredto receive a replaceable collection media assembly 100 and secure thecollection media assembly 100 in a preferred alignment within theinternal sensor portion 13, as described herein. In various embodiments,the collection media assembly dock element 200 may be disposed withinthe internal sensor portion 13 of the fluid composition sensor 10 whenthe sensor 10 is in a closed configuration. In various embodiments,wherein the fluid composition sensor 10 is configured in an openconfiguration so as to define an opening through which a replaceablecollection media assembly 100 and/or a removable fluid flow component 40may be removed, the collection media assembly dock element 200 may bedisposed within the internal sensor portion 13 proximate the opening ofthe sensor 10 to allow for the removal and/or replacement of areplaceable collection media assembly 100 arranged therein through saidsensor opening. In various embodiments, as illustrated in FIG. 4,wherein the fluid composition sensor 10 is configured such that theinterface between the upper and lower sensor housing portions 20, 30defines an at least substantially horizontal plane, the collection mediaassembly dock element 200 may be disposed about a top portion of thelower sensor housing 30 proximate said interface.

In various embodiments, the collection media assembly dock element 200may comprise a collection media assembly receptacle 210 in which areplaceable collection media assembly 100 may be inserted. As describedherein, the collection media assembly receptacle 210 may be embodied, atleast in part, by an outer frame having a geometry corresponding to thatof a collection media assembly 100 such that the collection mediaassembly 100 may be inserted therein and secured in a desired positionrelative one or more other components of the sensor. In variousembodiments, the collection media assembly receptacle 210 may beconfigured to restrict the lateral movement of the replaceablecollection media assembly 100 disposed therein relative collection mediaassembly dock element 200, wherein the lateral movement of thecollection media assembly 100 is movement in a direction that is atleast substantially perpendicular to a removal/insertion direction ofthe collection media assembly 100 (i.e. the direction in which thecollection media assembly 100 is removed from and/or inserted into thecollection media assembly receptacle 210). For example, one or moreportions of the collection media assembly receptacle 210, such as, forexample, one or more of the collection media assembly receptaclesidewalls, a peripheral alignment protrusion, and/or a bottom alignmentprotrusion 211, may engage the replaceable collection media assembly 100so as to stabilize the position of the replaceable collection mediaassembly 100 within the collection media assembly receptacle 210. Invarious embodiments, such a configuration may restrict the replaceablecollection media assembly 100 from moving in the x-y plane relative tothe imaging device, as discussed herein.

Further, in various embodiments, a collection media assembly dockelement 200 may comprise one or more alignment features positioned atleast substantially adjacent the collection media assembly receptacle210 and configured to engage a corresponding feature of a replaceablecollection media assembly 100 disposed within the receptacle 210. Forexample, in various embodiments, as discussed herein, the collectionmedia assembly dock element 200 may comprise a peripheral alignmentelement configured to extend from the collection media assembly dockelement 200 inward toward a collection media assembly 100 disposedtherein, the replaceable collection media assembly 100 having acorresponding recess configured to receive the peripheral alignmentelement therein. In such a circumstance, the recess defined within thereplaceable collection media assembly 100 may at least partiallysurround the peripheral alignment element such that as the collectionmedia assembly 100 begins to rotate in an angular direction relative tothe collection media assembly dock element 200, at least a portion ofthe replaceable collection media assembly 100 defining an edge of therecess engages the adjacent peripheral alignment element, which acts asa physical barrier to prevent the replaceable collection media assembly100 from moving in a radial direction relative to the collection mediaassembly dock element 200.

Additionally, as described above, the fluid composition sensor 10 may beconfigured such that when the sensor 10 is in a closed configuration,the upper sensor housing 20 may restrict the vertical movement (e.g., inthe z-direction) of the removable fluid flow component 40 disposedtherein by applying a vertical compression force to the fluid flowcomponent 40 such that the fluid flow component 40 is compressed in thevertical direction against an adjacent impactor nozzle. In variousembodiments, the aforementioned compression force generated by thehousing 11 and applied to the fluid flow component 40 may be transmittedto a replaceable collection media assembly 100 disposed within thecollection media assembly dock element 200 (e.g., the collection mediaassembly receptacle 210) so as to prevent the collection media assembly100 from moving in the vertical direction (e.g., in the z-direction)relative to the collection media assembly dock element 200 by pressingthe collection media assembly 100 against a constrained bottom surfaceof the collection media assembly dock element 200.

In various embodiments, the collection media assembly dock element 200may further comprise an imaging orifice extending through a thicknessthereof. The imaging orifice may be positioned within the collectionmedia assembly dock element 200 (e.g., the collection media assemblyreceptacle 210) so as to enable a clear line of sight between areceiving area of the collection media 131 (i.e. the portion of thecollection media 131 configured to receive particles from the volume offluid flowing through the sensor 10) disposed within the replaceablecollection media assembly 100 secured within the collection mediaassembly dock element 200 and an imaging device arranged within thelower sensor housing 30 below the collection media assembly dock element200. For example, the imaging orifice may be defined, at least in part,within a bottom surface of the collection media assembly dock element200 so as to facilitate the particle analysis functionality of the fluidcomposition sensor 10, as described herein, by enabling the imagingdevice to capture an image of the plurality of particles embedded withinthe receiving area of the collection media 131. In various embodiments,the imaging orifice may be configured such that the collection mediaassembly dock element 200 does not interfere with the field of view ofthe imaging device.

As described herein, the collection media assembly dock element 200 mayfurther comprise a transparent protective cover (e.g., transparentglass, transparent plastic, and/or the like) configured to cover theimaging orifice so as to protect the imaging device from contamination.A protective cover may be configured so as to allow the imaging deviceto maintain a line of sight to the collection media 131, as describedabove while physically isolating the imaging device from any fluidand/or particulate matter flowing through the sensor 10. For example, bypreventing the fluid and/or particulate matter flowing through thesensor 10 from interacting with the imaging device, the transparentprotective cover reduces the errors associated with the particleanalysis function that may be caused by the contamination of the imagingdevice. which may result in error. In various embodiments wherein thefluid composition sensor 10 is in an open configuration, a replaceablecollection media assembly 100 disposed within the collection mediaassembly dock element 200 may be removed from a particle collectionposition within the internal sensor portion 13 of the fluid compositionsensor 10. For example, the transparent protective cover may be arrangedsuch that it is accessible to a user upon the removal of the replaceablecollection media assembly 100. The transparent protective cover may beremoved from the collection media assembly dock element 200 tofacilitate the cleaning and/or replacement of the cover so as tominimize the risk of system inaccuracies caused by leftover particlesfrom a previous sample volume of fluid being disposed on the protectivecover within the field of view of the imaging device such that imagedistortion is created with respect to the imaging and analysis of anysubsequently examined particle samples.

In various embodiments, the collection media assembly dock element 200may be arranged within the internal sensor portion 13 (e.g., within thelower sensor portion 30) such that when the fluid composition sensor 10is in a closed configuration, at least a portion of a collection media131 of a replaceable collection media assembly 100 secured within thecollection media assembly dock element 200 may be within a field of viewof the imaging device 300. Further, in various embodiments wherein theimpactor nozzle is included as an inlet of the replaceable collectionmedia assembly 100, the collection media assembly dock element 200 maybe arranged within the internal sensor portion 13 such that the impactornozzle (e.g., central nozzle axis thereof) is at least substantiallyaligned with both the imaging device (e.g., the field of view) disposedwithin the lower sensor housing 30 and the outlet of the fluid flowcomponent 40, as described herein. Additionally, in such aconfiguration, the collection media assembly dock element 200 may bearranged within the internal sensor portion 13 such that when the fluidcomposition sensor 10 is in a closed configuration, a light beam 61emitted from an illumination source 60 may engage the portion of thecollection media 131 that is at least substantially aligned with thefield of view of the imaging device upon extending through both theinlet and the outlet of the impactor nozzle.

As described herein, the fluid composition sensor 10 comprises an uppersensor housing 20 and a lower sensor housing 30 that are connected toone another via a hinged connection 16 such that the sensor 10 may beopened by moving the upper sensor housing 20 about the hinges 16relative to the lower sensor housing 30. In various embodiments, thehinged connection of the fluid composition sensor 10 may at leastpartially anchor the relative motion between the between the uppersensor housing 20 and lower sensor housing 30 so as to facilitate therepeatability of properly aligning each of the various sensor componentsrespectively disposed within the two housing portions, as describedherein.

Alternatively, or additionally, the upper sensor housing 20 and lowersensor housing 30 of the fluid composition sensor 10 may be configuredto be completely detachable from one another, such that configuring thefluid composition sensor 10 in an open configuration comprises entirelydetaching one of the two aforementioned sensor portions 20, 30 from theother. In such a configuration, the fluid composition sensor 10 maycomprise one or more additional latch and/or fasting elements configuredto secure the upper sensor housing 20 to the lower sensor housing 30 ina closed sensor configuration. FIG. 5 illustrates a perspective view,and further a partial sectional view, of an exemplary fluid compositionsensor 10 according to an embodiment described herein. In particular,FIG. 5 illustrates an exemplary fluid composition sensor 10 that isconfigurable between at least an open sensor configuration and a closedsensor configuration and comprises an upper sensor housing 20 and alower sensor housing 30, wherein the upper sensor housing 20 isillustrated using a cutaway perspective view. The open sensorconfiguration of the exemplary fluid composition sensor 10 may bedefined by the upper sensor housing 20 and the lower sensor housing 30being completely detached from one another. In various embodiments, theupper sensor housing 20 and the lower sensor housing 30 may beconfigured such that when the exemplary fluid composition sensor 10 isin a closed configuration, the interface between the two sensor housingportions 20, 30 extends around at least a portion of the peripheral edgeof the housing 11 about an at least substantially horizontal planepositioned between the two sensor portions 20, 30.

The exemplary fluid composition sensor 10 may be configured such thatthe sensor 10 may be selectively arranged in a closed configuration byutilizing one or more corresponding interlocking engagement features(e.g., tabs, guided tracks, pins, and/or the like) disposed on the uppersensor housing 20 and the lower sensor housing 30, respectively. Forexample, each of the interlocking features may be disposed proximate therespective interface portions of the two sensor housing portions 20, 30such that upon the execution of, for example, a two-step attachmentaction, the upper sensor housing 20 may be secured to the lower sensorhousing 30 and arranged such that the removable fluid flow component 40disposed therein is aligned with an imaging device and at least aportion of the collection media 131 disposed within the lower sensorhousing 30, as described herein. In various embodiments, the removablefluid flow component 40 disposed therein may be aligned with the imagingdevice and at least a portion of the collection media 131 disposedwithin the lower sensor housing 30 about a vertical axis extendingthrough a central portion of the fluid composition sensor 10 or,alternatively, through a portion of the sensor positioned a distanceaway from the aforementioned central portion. In various embodiments,the fluid composition sensor 10 may be configured such that the two-stepattachment action may be defined by two actions that facilitate thearrangement of the sensor 10 in a closed configuration when executed insequence. Further, in various embodiments, the fluid composition sensor10 may be configured such that the sensor 10 may be rearranged to definean open configuration by executing the two actions of the two-stepattachment action in a reverse sequence. For example, in variousembodiments, the exemplary fluid composition sensor 10 may be configuredin a closed configuration using a two-step attachment action similar tothat that used to attach a camera lens to a single-lens reflex (SLR)camera or the sequential, bi-directional action required to open achild-resistant prescription pill bottle. The upper sensor housing 20may be attached to the lower sensor housing 30 so as to define a closedsensor configuration by positioning one or more of the engagementfeatures disposed about the upper sensor housing 20 relative to the oneor more corresponding engagement features of the lower sensor portion 30and rotating the upper sensor housing 20 about a central vertical axisof the fluid composition sensor 10 an angular distance of, for example,90 degrees. In various embodiments, the upper sensor housing 20 maycomprise one or more electronic components that may establish electroniccommunication with the internal control circuitry of the sensor 10 uponbeing rotated, for example, 90 degrees to a locked position.

In various embodiments, the upper sensor housing 20 comprises sensorfluid inlet embodied as an opening through which the fluid compositionsensor 10 may receive a volume of fluid from an ambient environment, ahandle 15, and a dust cap 14 that may be configured to mitigate theamount of ambient fluid that unintentionally enters the fluidcomposition sensor 10 through the fluid flow component inlet byproviding a physical cover that at least substantially isolates thefluid flow component inlet from the ambient environment. For example,the dust cover 14 may be integrated in to the housing 11 such that itmay be selectively moved between an open position and a closed position.Further, in various embodiments, the upper sensor housing 20 defines aninternal sensor portion 13 configured to receive a removable fluid flowcomponent 40. The removable fluid flow component 40 may be inserted intothe internal sensor portion 13 of the upper sensor housing 20 when thefluid composition sensor 10 is in an open configuration. For example,the removable fluid flow component 40 may be secured within the uppersensor housing 20 using one or more corresponding “snap-in” fasteningfeatures disposed about both the fluid flow component 40 and theinternal sensor portion 13, respectively. The upper sensor housing 20may be configured to maintain a desired alignment of the removable fluidflow component 40 within the internal sensor portion 13 using aforce-inducing element such as, for example, a torsional spring thatremains in contact with the fluid flow component 40 while allowing forthe rotation thereof. As shown, in various embodiments, the impactornozzle 112 of the fluid composition sensor 10 may be part of theremovable fluid flow component 40. For example, the impactor nozzle 112may define the fluid outlet of the fluid flow component 40.

In various embodiments, the lower sensor housing 30 may comprise a topsurface configured to at least partially isolate the various sensor 10components disposed within the lower sensor housing 30 from the ambientenvironment and a fluid inlet, which may be defined by an orificepositioned about the aforementioned top surface that is configured toreceive a volume of air from a fluid flow component 40 when the fluidcomposition sensor 10 is in a closed sensor configuration. As shown, theexemplary fluid composition sensor 10 is configured such that thecollection media may be positioned within the lower sensor housing 30 toreceive a plurality of particles from a volume of fluid dispensed fromthe outlet of the impactor nozzle (e.g., the fluid flow component 40).The collection media may be disposed upon a collection media assembly400 embodied as a disposable slide, as described in further detailherein. The fluid composition sensor 10 may be configured to receive adisposable slide 400 having a collection media 131 attached theretothrough an opening in the housing 11 and position the slide 400 at leastpartially within an internal sensor portion 13, such that the collectionmedia 131 is disposed within a fluid flow path of a volume of fluidtraveling through the sensor 10. As described herein, the fluidcomposition sensor 10 may be further configured to arrange the slide 400(e.g., the collection media) within the internal sensor portion 13 suchthat it may be aligned with an outlet of the impactor nozzle 112, animaging device 300, and an illumination source. In various embodiments,the fluid composition sensor may further comprise a slide ejectionbutton 410 configured to facilitate the removal of the disposable slide400 from the housing 11 of the sensor 10. In various embodiments, uponthe commencement of the particle collection functionality of the fluidcomposition sensor 10, as described herein, the sensor may be configuredto lock the slide ejection button 410 such that it will not function torelease the slide 400 disposed within the internal sensor portion 13until a determination is made, for example, by the controller that boththe particle collection and particle analysis functions have beencompleted.

FIGS. 6A-6B illustrate perspective views of an exemplary apparatus inaccordance with various embodiments. In particular, FIGS. 6A and 6B showa top perspective view and a bottom perspective view, respectively, ofan exemplary removable fluid flow component 40 according to variousembodiments described herein. In various embodiments, the removablefluid flow component 40 may be configured to receive a volume of fluidfrom a sensor fluid inlet through at least one fluid flow componentinlet 41A and may define at least a portion of a fluid flow path of thevolume of fluid whereby the volume of fluid may travel from the fluidflow component inlet 41A to a fluid flow component outlet 42. Theremovable fluid flow component 40 may be disposed within an internalsensor portion of an exemplary fluid composition sensor 10 and arrangedsuch that the at least one fluid flow component inlet 41A is positionedat least substantially proximate a sensor fluid inlet. As illustrated inFIG. 6A, in various embodiments, the at least one fluid flow componentinlet may comprise a first fluid flow component inlet 41A and a secondfluid flow component inlet 41B, each being configured to receive arespective volume of fluid.

In various embodiments, a removable fluid flow component 40 may includea light path orifice 43 comprising a channel extending through at leasta portion of the removable fluid flow component 40. For example, anillumination source, as described herein, may be positioned within aninternal sensor portion at least substantially adjacent an exteriorportion of the removable fluid flow component 40. The illuminationsource may emit a light beam in a direction at least substantiallytowards the collection media 131. In various embodiments, the light pathorifice 43 of the removable fluid flow component 40 may be configured toenable the light beam emitted from the illumination source to extendthrough at least a portion of the removable fluid flow component 40 tothe fluid flow component outlet 42 without being interrupted by aportion (e.g., a wall) of the removable fluid flow component 40. As suchthe configuration of the light path orifice 43 may correspond to that ofthe illumination source and the light beam emitted therefrom. Forexample, in various embodiments, the illumination source may be arrangedsuch that the light beam emitted therefrom extends in a direction thatis at least substantially coaxial with a central axis of the removablefluid flow component 40 (e.g., the fluid flow component outlet 42). Insuch an exemplary configuration, the light beam orifice 43 of theremovable fluid flow component 40 may similarly extend in a directioncoaxial with the central axis of the fluid flow component 40 between thesurface of the fluid flow component 40 adjacent the illumination sourceand the fluid flow component outlet 42. Further, the light beam orifice43 may be defined at least in part by a diameter that is at least aslarge as the corresponding diameter of the light beam and such thatsidewalls of the light beam orifice 43 (along a thickness of the fluidflow component 40) do not substantially interfere with the light beam(e.g., causing reflections of light which may create interference in thegenerated image once the light is received at the imaging device). Invarious embodiments, the diameter of the light beam orifice 43 may beeither constant or may vary based at least in part on the light beamhaving a variable diameter (e.g., a diverging light beam).

As shown in FIG. 6B, the fluid flow component outlet 42 may comprise apassage disposed at least substantially near a bottom surface of theremovable fluid flow component 40 through which a volume of fluidtraveling through the removable fluid flow component 40 may bedispensed. As described herein, the fluid flow component outlet 42 maybe configured so as to dispense a volume of fluid from the removablefluid flow component 40 in a direction at least substantially toward animpactor nozzle. For example, in various embodiments, the fluid flowcomponent outlet 42 may be configured so as to be at least substantiallyaligned with a nozzle inlet of an impactor nozzle. Further, in variousembodiments, the size and shape of the fluid flow component outlet 42may be at least substantially similar to that of the nozzle inlet. Asdescribed herein, in various embodiments, the fluid composition sensor10 may be configured to apply a compression force to the removable fluidflow component 40, at least in part, to create a secured seal at thefluid flow component outlet 42 so as to ensure that the sample volume offluid flowing from the fluid flow component outlet 42 to the impactornozzle remains fluidly isolated from a volume of ambient fluid. Further,in various embodiments, the impactor nozzle of the fluid compositionsensor 10 may be connected to the removable fluid flow component 40 soas to define a singular sensor component, as described herein.

The removable fluid flow component 40 may be disposed within an internalsensor portion of the fluid composition sensor 10. As described herein,the removable fluid flow component 40 may be removed from the internalsensor portion to facilitate the cleaning and/or replacement of theremovable fluid flow component 40 in order to decrease the amount ofundesired particulate matter that has accumulated therein and minimizethe risk of system error caused by contamination. In variousembodiments, the removable fluid flow component 40 may be comprised of aplurality of separable components that fit together to collectivelydefine the removable fluid flow component 40. In such a circumstance,the removable fluid flow component 40 may be at least partiallydisassembled such that at least a portion of the plurality of separablecomponents may be cleaned as individually. For example, disassemblingthe removable fluid flow component 40 prior to the cleaning process maymake accessible one or more areas that could not traditionally bereached in a singular component.

In various embodiments the removable fluid flow component 40 maycomprise a light trap configured to absorb light so as to minimize theamount of light reflected off of a component within an internal sensorportion and toward a field of view of the imaging device, which mayproduce image interference that may at least partially obscure one ormore features of the one or more particles disposed within thecollection media 131, as described herein.

Receipt of Replaceable Collection Media Assembly by Fluid CompositionSensor

FIG. 7 illustrates an exploded view of various components of anexemplary apparatus in accordance with various embodiments describedherein. In particular, FIG. 7 illustrates an exploded view of anexemplary embodiment wherein a fluid composition sensor 10 comprises animaging device 300, a collection media assembly dock element 200, atransparent protective cover 201, and a replaceable collection mediaassembly 100. As illustrated, each of the aforementioned sensorcomponents may be at least substantially coaxially aligned along acentral vertical axis extending between the imaging device 300, animaging orifice disposed within the collection media assembly dockelement 200, the a field of view of the imaging device on a collectionmedia of the particle collection slide 130, and both the nozzle outletand the nozzle inlet of the impactor nozzle disposed about a top of theof an upper cassette portion of the replaceable collection mediaassembly 100. In various embodiments, as described herein, the imagingdevice 300 (e.g., a field of view of the imaging device 300) and areceiving area of the collection media 131 disposed within thereplaceable collection media assembly 100 may be aligned about avertical axis extending through a central portion of the fluidcomposition sensor or, alternatively, through a portion of the sensorpositioned a distance away from the aforementioned central portion.Further, in various embodiments, an impactor nozzle, an illuminationsource, and/or an imaging orifice of the collection media assembly dockelement may be similarly aligned along an at least substantially similarvertical axis.

In various embodiments, the replaceable collection media assembly 100may be embodied as, for example, a replaceable cassette comprising anupper cassette portion 110, a lower cassette portion 120, and a particlecollection slide 130. In various embodiments, the upper cassette portion110 and the lower cassette portion 120 may collectively define acollection media housing configured to receive and secure the particlecollection slide 130 therein. As described herein, the upper cassetteportion 110 may be configured to receive a volume of fluid and/or directthe volume of fluid toward a receiving area of the collection mediadisposed upon the particle collection slide 130 such that at least aportion of the particles within the volume of fluid received by theupper cassette portion become embedded in the collection media. Further,the lower cassette portion 120 may comprise an opening extendingtherethrough so as to enable an image to be taken of the plurality ofparticles disposed on the particle collection slide 130 from theunderside of the replaceable collection media assembly 100.

As described herein, one or both of the upper cassette portion 110 andthe lower cassette portion 120 may be made from one or more of a varietyof materials having any of a variety of different physical properties(e.g., surface finishes, colors). For example, in various embodiments,at least a portion of one or both of the upper cassette portion 110 andthe lower cassette portion 120 may comprise a transparent material.Further, in various embodiments, at least a portion of one or both ofthe upper cassette portion 110 and the lower cassette portion 120 maycomprise a transparent material, such as, for example, glass.Alternatively, or additionally, in various embodiments, at least aportion of one or both of the upper cassette portion 110 and the lowercassette portion 120 may be made from a non-reflective material having ablack (e.g., matte black) finish so as to reduce and diffuse any opticalreflections within and/or near the replaceable collection media assembly100. For example, in various embodiments, one or more surfaces of thereplaceable collection media assembly housing may comprise a matte SPIC-2 finish. In various embodiments, at least a portion of one or both ofthe upper cassette portion 110 and the lower cassette portion 120 maycomprise a conductive portion that is either made from astatic-dissipative material or has a static-dissipative surfacetreatment applied thereto. Further, in various embodiments, at least aportion of one or both of the upper cassette portion 110 and the lowercassette portion 120 may comprise a hydrophobic material or has ahydrophobic surface treatment applied thereto. Alternatively, oradditionally, in various embodiments, at least a portion of one or bothof the upper cassette portion 110 and the lower cassette portion 120 maycomprise a hygroscopic material or has a hygroscopic surface treatmentapplied thereto. In various embodiments, at least a portion of one orboth of the upper cassette portion 110 and the lower cassette portion120 may comprise an oleophobic material or has an oleophobic surfacetreatment applied thereto. Alternatively, or additionally, in variousembodiments, at least a portion of one or both of the upper cassetteportion 110 and the lower cassette portion 120 may comprise anoleoscopic (e.g., oleophilic) material or has an oleoscopic (e.g.,oleophilic) surface treatment applied thereto.

In various embodiments, the fluid composition sensor 10 may furthercomprise a collection media assembly dock element 200 configured toreceive a replaceable collection media assembly 100 and secure thecollection media assembly 100 in a preferred alignment within theinternal sensor portion. For example, the collection media assembly dockelement 200 may be embodied as a tray (e.g., inset relative to the lowersensor housing 30) comprising a collection media assembly receptacle 210designed to include one or more geometric features corresponding to thephysical configuration of the replaceable collection media assembly 100such that a replaceable collection media assembly 100 may be insertedtherein and secured in a desired position relative one or more othercomponents of the sensor 10. In various embodiments, the imaging device300 may be operatively attached (e.g., via a printed circuit board) to abottom surface of the collection media assembly dock element 200 andpositioned directly adjacent an imaging orifice extending through thecollection media assembly dock element 200 such that the imaging device300 may have an unimpeded line of sight to the receiving area of theparticle collection slide 130, which may be at least substantiallyaligned with an illumination source, as described herein. Such aconfiguration facilitates the particle analysis functionality of thefluid composition sensor 10, as described herein, by enabling theimaging device 300 to capture an image of the plurality of particlesembedded within the receiving area of the particle collection slide 130(e.g., the collection media) while the replaceable collection mediaassembly 100 remains secured within the collection media assembly dockelement 200. In various embodiments, the collection media assembly dockelement 200 may further comprise a transparent protective cover 201configured to cover the imaging orifice at the top surface of thecollection media assembly dock element 200 so as to protect the imagingdevice 300 from contamination.

In various embodiments, one or more portions of the collection mediaassembly receptacle 210, such as, for example, one or more of thecollection media assembly receptacle sidewalls, a peripheral alignmentprotrusion, and/or a bottom alignment protrusion, may engage thereplaceable collection media assembly 100 so as to prevent thecollection media assembly 100 within the collection media assemblyreceptacle 210 from moving in the x-y plane relative to the imagingdevice 300. Further, in various embodiments, a collection media assemblydock element 200 may comprise one or more alignment features positionedat least substantially adjacent the collection media assembly receptacle210 and configured to engage a corresponding feature of a replaceablecollection media assembly 100 disposed within the receptacle 210 so asto facilitate the angular alignment of the replaceable collection mediaassembly 100 and to prevent the replaceable collection media assembly100 from moving in a radial direction relative to the collection mediaassembly dock element 200. For example, such alignment features may bean alignment key and corresponding slot, as shown in the illustratedembodiments, a non-round portion of the perimeter of the replaceablecollection media assembly 100, and/or the like. Additionally, asdescribed in further detail herein, the replaceable collection mediaassembly may be further constrained in the vertical direction (e.g.,z-direction) based at least in part on the configuration of the fluidcomposition sensor 10 and a downward vertical force transmitted throughone or more sensor components to the replaceable collection mediaassembly 100 disposed within the collection media assembly receptacle210 such that the replaceable collection media assembly 100 is pressedagainst a constrained bottom surface of the collection media assemblydock element 200. As described herein, the collection media assemblydock element 200 may be configured within the fluid composition sensor10 such that a replaceable collection media assembly 100 insertedtherein may prevented from moving relative to the imaging device 300 ineach of the x-direction, the y-direction, the z-direction, and theangular direction.

Replaceable Collection Media Assembly

As shown in FIGS. 8-12B, the fluid composition sensor 10 may comprise areplaceable collection media assembly 100. In various embodiments, areplaceable collection media assembly 100 may be configured to bedisposed within an internal sensor portion of a fluid composition sensorand positioned within a fluid flow path defined by the sensor. Asdescribed herein, a volume of fluid comprising a plurality of particlesand traveling along the fluid flow path may pass across a collectionmedia of the replaceable collection media assembly 100 such that atleast a portion of the plurality of particles within the volume of fluidbecome embedded within the collection media. In various embodiments, areplaceable collection media assembly 100 disposed within the fluidcomposition sensor may be removed from, for example, a particlecollection position within the internal sensor portion of the fluidcomposition sensor. For example, upon determining that at leastsubstantially the entirety of a sample volume of fluid has passed acrossa surface of the collection media and that the one or more images of theparticles needed to enable the particle analysis function of the sensor10 have been captured by an imaging device, the replaceable collectionmedia assembly 100 may be removed from the internal sensor portion ofthe fluid composition sensor. Further, as described herein, the removedreplaceable collection media assembly 100 may be replaced with adifferent, unused replaceable collection media assembly 100.

FIG. 8 illustrates a perspective view of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein. In particular, FIG. 8 illustrates an unusedreplaceable collection media assembly 100, wherein the replaceablecollection media assembly 100 is embodied as a replaceable cassette. Asdescribed herein, a replaceable collection media assembly 100 maycomprise a collection media and a collection media housing (e.g., aframe element) configured to receive and secure the collection media(e.g., a particle collection slide upon which the collection media maybe disposed) relative to the housing. Further, in various embodiments, acollection media housing may be configured facilitate the transportationand positioning of the replaceable collection media assembly 100 withina fluid composition sensor.

As illustrated in FIG. 8, a replaceable collection media assembly 100may comprise an upper cassette portion 110, a lower cassette portion120, and a particle collection slide (not shown). The upper cassetteportion 110 and lower cassette portion 120 may define correspondingalignment features for assembly of the cassette 100. For example, theupper cassette portion 110 may comprise a protruding edge along a lowerside of the upper cassette portion 110 that is configured to engage acorresponding inset edge along the upper side of the lower cassetteportion 120, thereby enabling the upper cassette 110 to engage the lowercassette portion 120. In various embodiments, the upper cassette portion110 may be secured relative to the lower cassette portion 120 via any ofa variety of fastening configurations, such as tape (e.g., around anexterior perimeter of the cassette 100), adhesive, ultrasonic welding,and/or the like).

In various embodiments, the upper cassette portion 110 and the lowercassette portion 120 may collectively define a collection media housingconfigured to receive and secure the particle collection slide therein.Specifically, as shown the lower cassette portion 120 may define areceiving portion for the particle collection slide (e.g., an insetportion having a size and/or shape corresponding to the size and shapeof the particle collection slide). The receiving portion may be an insetportion having a depth corresponding to the thickness of the particlecollection slide, and having length and width dimensions correspondingto the length and width, respectively, of the particle collection slide,such that the particle collection slide is entrapped within the cassette100 when assembled to impede undesired movement therein. As illustrated,the replaceable collection media assembly 100 may define an at leastsubstantially circular perimeter. In various embodiments, the uppercassette portion 110 may comprise a fluid inlet configured to receive avolume of fluid. Further, as illustrated, the impactor nozzle 112 of thefluid composition sensor 10 may be part of the replaceable collectionmedia assembly 100. For example, the impactor nozzle 112 may bepositioned on a top portion of the replaceable collection media assembly100 so as to define a portion of the upper cassette portion 110. In sucha configuration, the impactor nozzle 112 may define the fluid inlet ofthe replaceable collection media assembly 100 through which thereplaceable collection media assembly 100 may be configured to receive avolume of fluid from a removable fluid flow component positionedupstream within the fluid composition sensor. The impactor nozzle 112may be further configured to direct the volume of fluid toward thecollection media of the replaceable collection media assembly 100 suchthat at least a portion of the particles within the volume of fluidreceived by the upper cassette portion become embedded within thecollection media.

As described herein, in various embodiments, both the upper cassetteportion 110 and the lower cassette portion 120 may comprise one or morealignment features configured to assist with the alignment and/orpositioning of the replaceable collection media assembly 100 within thein the fluid composition sensor. For example, as illustrated in FIG. 8,both the both the upper cassette portion 110 and the lower cassetteportion 120 define a peripheral alignment recess 113, 123 extending froma peripheral edge inward toward a central portion thereof. Theperipheral alignment recesses 113, 123 may comprise a portion of theupper and lower cassette portions 110, 120, respectively, that has beencut away (e.g., a slit) such that they may be configured to receive acorresponding peripheral alignment element extending from a collectionmedia assembly dock element 200 in which the replaceable collectionmedia assembly 100 is disposed inward toward the central portion of thereplaceable collection media assembly 100. The upper peripheralalignment recess 113 and the lower peripheral alignment recess 123 maybe at least substantially aligned relative to one another and may eachreceive a portion of the peripheral alignment element so as to align theupper and lower cassette portions 110, 120, respectively, in a desiredangular configuration relative to the collection media assembly dockelement 200 (and thus, to an imaging device positioned adjacent thereto,as described herein). In such a configuration, the peripheral alignmentrecesses 113, 123 may at least partially surround the peripheralalignment element of the collection media assembly dock element 200. Inan exemplary circumstance wherein the collection media assembly 100begins to rotate in an angular direction relative to the collectionmedia assembly dock element 200, for example, at least a portion of thereplaceable collection media assembly 100 defining an edge of theperipheral alignment recesses 113, 123 may engage the adjacentperipheral alignment element, thereby acting acts as a physical barrierpreventing the replaceable collection media assembly 100 from moving inan angular direction relative to the collection media assembly dockelement 200.

In various embodiments, a fluid composition sensor may be susceptible toincreased inaccuracies over time, for example, as a number of particlescollected within a replaceable collection media assembly 100 changes asa result of the increased number of particles disposed therein. Thus,the collection media assembly 100 and/or one or more components thereofmay be replaceable. In various embodiments, replacing a replaceablecollection media assembly 100 and/or one or more components thereof maycomprise removing the assembly from the fluid composition sensor andreplacing the replaceable collection media assembly 100 and/or the oneor more components thereof with a substantially similar part. Forexample, in order to minimize the risk of system inaccuracies caused byleftover particles from a previous sample volume of fluid being disposedwithin a collection media prior to the start of the particle collectionfunction of the sensor, the replaceable collection media assembly 100comprising the used collection media may be removed from the sensor andreplaced with an unused replaceable collection media assembly 100. Invarious embodiments, as illustrated in FIG. 8, an unused replaceablecollection media assembly 100 may comprise a sealed cover 114, such as,for example, an adhesive sticker, configured to cover an entirety of thefluid inlet of replaceable collection media assembly 100. Additionally,in various embodiments, an unused replaceable collection media assembly100 may further comprise a sealed cover 114 configured to cover anentirety of the fluid outlet of the replaceable collection mediaassembly 100, defined at least in part by an opening along a bottomportion of the collection media assembly 100. In such a configuration,the collection media of the replaceable collection media assembly 100may be at least substantially isolated from an ambient environment suchthat the risk of contamination of the collection media prior to beinginserted into the fluid composition sensor is minimized. As illustrated,the sealed cover 114 of the replaceable collection media assembly 100may comprise a singular adhesive element with various portionsconfigured to cover one of the fluid inlet and fluid outlet of thereplaceable collection media assembly 100 and an intermediary connectionportion extending therebetween through the peripheral alignment recesses113, 123.

FIG. 9 illustrates an exploded view of various components of anexemplary apparatus in accordance with various embodiments describedherein. In particular, FIG. 9 illustrates an exploded view of anexemplary replaceable collection media assembly 100. As describedherein, the replaceable collection media assembly 100 of a fluidcomposition sensor may be embodied as, for example, a replaceablecassette comprising an upper cassette portion 110, a lower cassetteportion 120, and a particle collection slide 130. The upper cassetteportion 110 and the lower cassette portion 120 may collectively define acollection media housing configured to receive and secure the particlecollection slide 130 therein. As described herein, the upper cassetteportion 110 may be configured to receive a volume of fluid, for example,through an impactor nozzle 112 (e.g., via a nozzle inlet) positioned ata top portion thereof, and/or direct the volume of fluid toward areceiving area of the collection media 131 disposed upon the particlecollection slide 130 such that at least a portion of the particleswithin the volume of fluid received by the upper cassette portion 110become embedded in the collection media.

In various embodiments, the particle collection slide 130 may comprise atransparent substrate 132 having a collection media 131 on at least aportion of an upper surface thereof. As described herein, the collectionmedia 131 may be configured to receive one or more particles of aplurality of particles via interaction with a volume of fluid travelingthrough a fluid composition sensor along a fluid flow path. In variousembodiments, the collection media 131 may comprise a receiving surfaceconfigured to face toward an impactor nozzle 112, and a backside thatmay be positioned at least substantially adjacent (e.g., secureddirectly to) the transparent substrate 132. The receiving surface of thecollection media 131 may comprise a receiving area defining the portionof the collection media 131 that, based at least in part on thearrangement of the collection media 131 relative to the nozzle outlet ofan impactor nozzle 112, is configured to receive particles from thevolume of fluid flowing through the sensor 10. Further, the collectionmedia 131 may have a thickness of at least substantially between about10 and about 1000 microns, (e.g., 100 microns) defined by the distancebetween the receiving surface and the backside. In various embodiments,the collection media 131 may comprise a material suitable to stop one ormore particles of a plurality of particles traveling at a velocity intothe receiving surface before the particle reaches the backside, suchthat the one or more particles of the plurality of particles areembedded within the collection media at a distance along the thicknessof the collection media 131. For example, in various embodiments, thecollection media may comprise an adhesive (i.e. sticky) material, suchas a gel.

In various embodiments, the replaceable collection media assembly 100may comprise a plurality of components. For example, as illustrated inFIG. 9, the upper cassette portion 110, the lower cassette portion 120and the particle collection slide 130 are three distinct components ofthe replaceable collection media assembly 100. Alternatively, in variousembodiments, the particle collection slide 130 may be molded into thelower cassette portion 120 such that the replaceable collection mediaassembly 100 may comprise two distinct components that may be piecedtogether to form a singular cassette. Further, the upper cassetteportion 110 and the lower cassette portion 120 may be molded togetherinto a singular frame element. In such a circumstance the singular framemay comprise one or more openings configured to receive the particlecollection slide 130 such that it may be properly positioned within thesingular frame, as described herein.

In various embodiments, the lower cassette portion 120 of thereplaceable collection media assembly 100 may comprise one or morefeatures configured to receive the particle collection slide 130 and atleast partially secure the slide 130 in a preferred arrangement adjacenta top portion thereof. For example, the lower cassette portion mayreceive and secure the particle collection slide 130 using a recessedshelf 122 embodied as an indention in a top surface of the lowercassette portion, the recessed shelf 122 having a shape and size thatare at least substantially similar to those of the particle collectionslide 130. Further, the lower cassette portion 120 may comprise anopening 124 extending therethrough so as to enable an image to be takenof the plurality of particles disposed on the particle collection slide130 from the underside of the replaceable collection media assembly 100.Further, the opening 124 of the lower cassette portion 120 may enable avolume of fluid to flow through the replaceable collection mediaassembly 100 to a fluid outlet thereof. As described herein, when thereplaceable collection media assembly 100 is disposed within a fluidcomposition sensor, at least a portion of the opening 124 of the lowercassette portion 120 may be aligned with the receiving area of thecollection media 131 and a field of view of an imaging device of thefluid composition sensor.

In various embodiments, the upper cassette portion 110 and the lowercassette portion 120 may be configured to be assembled together suchthat the particle collection slide 130 arranged on the lower cassetteportion 120 is secured therebetween. In various embodiments, the upperand lower cassette portions 110, 120 may each have respective attachmentfeatures corresponding to the attachment features of the other cassetteportion such that the two cassette portions 110, 120 assembled andsecured together. For example, the one or more attachment features maycomprise one or more geometric features (e.g., protrusions ridges,indentions, ad/or the like) configured to facilitate a semi-permanentengagement between the two cassette portions 110, 120. In variousembodiments, upon being assembled together with a particle collectionslide 130 arranged therebetween, the upper cassette assembly 110 and thelower cassette assembly 120, may be collectively configured to at leastsubstantially fully constrain the particle collection slide 130 suchthat the slide cannot move in any direction relative to either the upperor lower cassette portions 110, 120.

FIGS. 10A-10B illustrate a perspective view of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein. In particular, FIGS. 10A and 10B show a topperspective view and a bottom perspective view, respectively, of a lowercassette portion 120 of an exemplary replaceable collection mediaassembly 100 according to various embodiments described herein. Thelower cassette portion 120 of the replaceable collection media assembly100 may comprise a frame element defining at least a portion of acollection media housing. In various embodiments, the lower cassetteportion 120 may be configured to receive and secure a particlecollection slide. For example, the lower cassette portion may compriseone or more features configured to receive the particle collection slideand at least partially secure the slide in a preferred arrangementadjacent a top portion thereof. As illustrated in FIG. 9, the lowercassette portion 120 may receive the particle collection slide using arecessed shelf 122 embodied as an indention in a top surface of thelower cassette portion 120. The recessed shelf 122 may be defined atleast in part by perimeter sidewalls extending around an outer boundarythereof so as to at least partially constrain the movement of a particlecollection slide disposed therein. The recessed shelf 122 may have ashape and size that are at least substantially similar to those of theparticle collection slide. In various embodiments, the recessed shelf122 may be configured to extend across an opening 124 of the lowercassette portion 120, such that the recessed shelf 122 defines twodistinct shelf portions located on either side of the opening 124, eachconfigured to receive a portion of the particle collection slide. Insuch a configuration, the recessed shelf of the lower cassette portion120 is configured such that a particle collection side disposed thereinmay extend over at least a portion of the opening 124.

As described herein, an opening 124 of the lower cassette portion 120may extend through the lower cassette portion 120 in a substantiallyvertical direction so as to enable an underside of a particle collectionslide positioned within the lower cassette portion 120 (e.g., aplurality of particles embedded within a collection media disposed onthe particle collection slide) to be visible from beneath thereplaceable collection media assembly 100. As described herein, such aconfiguration may allow an imaging device positioned beneath areplaceable collection media assembly 100 within a fluid compositionsensor to capture an image of the plurality of particles embedded in thecollection media of the replaceable collection media assembly 100.Further, the opening 124 of the lower cassette portion 120 may enable avolume of fluid received by the replaceable collection media assembly100 to flow therethrough to a fluid outlet of the replaceable collectionmedia assembly 100 upon passing across at least a portion of a surfacethe collection media. For example, wherein the recessed shelf 122 may beconfigured to extend across an opening 124 of the lower cassette portion120, the volume of fluid may flow through one of two distinct openingportions 124A, 124B located on either side of the particle collectionslide. In various embodiments, when the replaceable collection mediaassembly 100 is disposed within a fluid composition sensor, at least aportion of the opening 124 of the lower cassette portion 120 may be atleast substantially aligned with the receiving area of the collectionmedia and a field of view of an imaging device of the fluid compositionsensor.

As described herein, the lower cassette portion 120 may be configuredsuch that it may be assembled together with an upper cassette portion inorder to define a collection media housing. In various embodiments, thelower cassette portion 120 may comprise one or more attachment featuresconfigured to facilitate the connection between the lower cassetteportion 120 and the upper cassette portion. For example, the one or moreattachment features may comprise one or more geometric features (e.g.,protrusions ridges, indentions, ad/or the like) configured to facilitatea semi-permanent engagement of the lower cassette portion 120 with theupper cassette portion. As illustrated in FIG. 10A, the one or moreattachment features of the lower cassette portion 120 may comprise ageometric profile, such as, for example, a ridge, extending around atleast a portion of the perimeter of the lower cassette portion 120. Invarious embodiments, the one or more attachment features of the lowercassette portion 120 may correspond to at least one of the attachmentfeatures defined by the upper cassette portion so as to facilitate theassembly of the lower cassette portion 120 to the upper cassette portionin a secured configuration.

As illustrated in FIG. 10B, the lower cassette portion 120 may comprisean interior cavity defined by the bottom surface and/or sidewallsthereof. In various embodiments, the bottom surface of the lowercassette portion 120 may be defined at least in part by one or moregeometric features 121 so as to create an interior cavity profilecorresponding to the profile of at least a portion of a collection mediaassembly dock element disposed within a fluid composition sensor. Thelower cassette portion 120 may be configured to facilitate the insertionand alignment of the replaceable collective media assembly 100 withinthe collection media assembly dock element based at least in part on theinterior cavity and the one or more geometric features 121 arrangedtherein. For example, in various embodiments wherein a collection mediaassembly dock element comprises a bottom alignment protrusion extendingupward into a collection media assembly receptacle from a bottom surfacethereof, the lower cassette portion 120 may be configured to receive thebottom alignment protrusion within the interior cavity such that the oneor more geometric features 121 therein may engage the bottom alignmentprotrusion so as to stabilize the position of the replaceable collectionmedia assembly 100 within the collection media assembly receptacle. Invarious embodiments, the configuration of the lower cassette portion120, such as, for example, the arrangement of geometric features 121within the interior cavity, sidewall length, and/or the like, may besuch that when the lower cassette portion 120 is disposed within acollection media assembly dock element in a fluid composition sensor, aparticle collection slide secured to the lower cassette assembly 120 maybe positioned at a predetermined distance away from an imaging device inorder to optimize a particle analysis function of sensor, as describedherein.

FIGS. 11A-11B illustrate perspective views of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein. In particular, FIGS. 11A and 11B show a topperspective view and a bottom perspective view, respectively, of anupper cassette portion 110 of an exemplary replaceable collection mediaassembly 100 according to various embodiments described herein. Invarious embodiments, the upper cassette portion 110 may define a portionof a replaceable collection media assembly 100 that is configured toreceive a volume of fluid traveling through a fluid composition sensorand direct the volume of air towards a collection media. As describedherein, the upper cassette portion 110 may be configured such that itmay be assembled together with a lower cassette portion in order todefine a collection media housing. In various embodiments, the uppercassette portion 110 may comprise one or more attachment featuresconfigured to facilitate the connection between the upper cassetteportion 110 and the lower cassette portion. For example, the one or moreattachment features may comprise one or more geometric features (e.g.,protrusions ridges, indentions, and/or the like) configured tofacilitate a semi-permanent engagement of the upper cassette portion 110with the lower cassette portion. As illustrated in FIG. 11B, the one ormore attachment features of the upper cassette portion 110 may comprisea geometric profile, such as, for example, an outer flange, extendingaround at least a portion of the perimeter of the upper cassette portion110. In various embodiments, the one or more attachment features of theupper cassette portion 110 may correspond to at least one of theattachment features defined by the lower cassette portion so as tofacilitate the assembly of the upper cassette portion 110 to the lowercassette portion in a secured configuration.

As illustrated in FIGS. 11A-11B, the upper cassette portion 110 may beconfigured to include the impactor nozzle 112 of a fluid compositionsensor. For example, the impactor nozzle 112 may be positioned on a topportion of the upper cassette portion 110. In such a configuration, theimpactor nozzle 112 may define the fluid inlet 111 of the upper cassetteportion 110 through which the upper cassette portion 110 may beconfigured to receive a volume of fluid from, for example, a removablefluid flow component positioned upstream within the fluid compositionsensor. For example, the fluid inlet 111 of the upper cassette portion110 may be defined by the outlet of the impactor nozzle 112. In variousembodiments, the impactor nozzle 112 may be further configured to directthe volume of fluid toward particle collection slide (e.g., a receivingface of a collection media arranged on the particle collection slide)disposed within the replaceable collection media assembly 100 such thatat least a portion of the particles within the volume of fluid receivedby the upper cassette portion 110 become embedded within the collectionmedia. The impactor nozzle 112 may extend from a top portion of theupper cassette portion 110 into the interior portion of the uppercassette portion 110 such that when the upper cassette portion 110 isattached to a lower cassette portion with a particle collection slidedisposed therebetween, the fluid inlet 111 of the upper cassette portion(e.g., the impactor nozzle outlet) is positioned at a predetermineddistance away from the particle collection slide (e.g., a receiving faceof a collection media disposed on the particle collection slide) inorder to optimize a particle collection function of sensor, as describedherein.

FIGS. 12A-12B illustrate perspective views of various exemplaryreplaceable collection media assemblies in accordance with variousembodiments described herein. In particular, FIGS. 12A-12B illustratereplaceable collection media assemblies 100 embodied as replaceablecassettes comprising various configurations. In various embodiments, areplaceable collection media assembly 100 may be configured tofacilitate the insertion of a collection media disposed within acollection media housing into a fluid composition sensor in a particulararrangement relative to an imaging device and/or an impactor nozzle 112in order to facilitate the particle collection and particle analysisfunctions of the sensor, as described herein. Accordingly, in variousembodiments, the replaceable collection media assembly 100 may beconfigured based at least in part on one or more components disposedwithin the fluid composition sensor with which the replaceablecollection media assembly 100 may interact.

For example, as described herein, the replaceable collection mediaassembly 100 may be configured to enable the insertion thereof into acollection media assembly dock element and facilitate the repeatabilityof the proper alignment thereof within the fluid construction sensor.For example, the replaceable collection media assembly 100 may compriseone or more alignment features configured to engage one or more othercomponents within the sensor so as to facilitate the linear alignmentand/or the angular alignment of the replaceable collection mediaassembly 100 relative to the collection media assembly dock element. Asillustrated in FIGS. 12A and 12B, for example, the replaceablecollection media assembly 100 may define an asymmetric (e.g.,non-circular) perimeter, such as, for example, a triangular orrectangular perimeter, respectively. In such a configuration, andwherein the collection media assembly dock element disposed within thefluid composition sensor comprises a substantially similar shape, thereplaceable collection media assembly 100 may only fit into thecollection media assembly dock element in an angular configuration thatensures proper alignment of the replaceable collection media assembly100 (e.g., the collection media within the replaceable collection mediaassembly) within the sensor, as described in further detail herein.

Further, in various embodiments wherein an impactor nozzle 112 of thefluid composition sensor is included as a distinct component of thesensor or as a part of, for example, a removable fluid flow componentdisposed within the sensor, the replaceable collection media assembly100 may be configured without an impactor nozzle. In such acircumstance, as illustrated in FIG. 12B, the fluid inlet 111 of thereplaceable collection media assembly 100 may be defined by the uppercassette portion 110. The fluid inlet 111 may be configured such thatthe volume of fluid passes therethrough in a fluid flow direction atleast substantially perpendicular to the collection media. In such anexemplary circumstance, the upper cassette portion 110 may be configuredsuch that when the upper cassette portion 110 and the lower cassetteportion 120 are attached to one another with a particle collection slidedisposed therebetween, the fluid inlet 111 of the upper cassette portion110 is positioned at a predetermined distance away from the particlecollection slide (e.g., a receiving face of a collection media disposedon the particle collection slide). The fluid inlet 111 may be defined atleast in part by the dimensions 111A and 111B so as direct the volume offluid toward an area on a receiving face of a collection media that isentirely within a field of view of an imaging device, as describedherein. For example, dimensions 111A, 111B may be configured based atleast in part on an aspect ratio of the imaging device.

FIG. 13 illustrates a perspective view of an exemplary collection mediaassembly dock element in accordance with various embodiments describedherein. In various embodiments, a collection media assembly dock element200 may be configured to receive a replaceable collection media assemblyand secure the collection media assembly in a preferred alignment withininternal sensor portion of a fluid composition sensor. As illustrated inFIG. 13, the collection media assembly dock element 200 may be embodiedas a tray comprising a collection media assembly receptacle 210 designedto include one or more geometric features corresponding to the physicalconfiguration of a replaceable collection media assembly such that thereplaceable collection media assembly may be inserted therein andsecured in a desired position relative one or more other components ofthe sensor. In various embodiments, the collection media assembly dockelement 200 may be configured such that an imaging device may beoperatively attached (e.g., via a printed circuit board) to a bottomsurface thereof. For example, an imaging device operatively attached tothe collection media assembly dock element 200 may be positioneddirectly adjacent an imaging orifice 212 extending through thecollection media assembly dock element 200 such that the imaging devicemay have an unimpeded line of sight through the collection mediaassembly dock element 200. In such a configuration, the collection mediaassembly dock element 200 (e.g., the imaging orifice 212) facilitatesthe particle analysis functionality of the fluid composition sensor, asdescribed herein, by enabling an imaging device to capture an image of areplaceable collection media assembly 100 while the replaceablecollection media assembly 100 remains secured within the collectionmedia assembly dock element 200.

In various embodiments, one or more portions of the collection mediaassembly receptacle 210, such as, for example, one or more of thecollection media assembly receptacle sidewalls, a peripheral alignmentprotrusion 213, and/or a bottom alignment protrusion 211, may engage areplaceable collection media assembly disposed therein so as to preventthe replaceable collection media assembly from moving in the x-y planerelative to the collection media assembly dock element 200. For example,the bottom alignment protrusion 211 may be configured to extend upwardinto a collection media assembly receptacle 210 from a bottom interiorsurface thereof. In such a configuration, wherein a replaceablecollection media assembly 100 is positioned within the collection mediaassembly receptacle 210, the bottom alignment protrusion 211 may beconfigured to protrude into an interior cavity of the lower cassetteportion of the removable collection media assembly so as to engage oneor more of a bottom surface, a sidewall, and a geometric protrusionthereof in order to stabilize the position of the replaceable collectionmedia assembly within the collection media assembly receptacle.

Further, as described herein, the collection media assembly dock element200 may comprise one or more alignment features positioned at leastsubstantially adjacent the collection media assembly receptacle 210 andconfigured to engage a corresponding feature of a replaceable collectionmedia assembly disposed within the receptacle 210. The one or morealignment features may facilitate the angular alignment of a replaceablecollection media assembly and to prevent the replaceable collectionmedia assembly from moving, for example, in an angular directionrelative to the collection media assembly dock element 200. In variousembodiments, as described herein, the collection media assembly dockelement 200 may be configured within a fluid composition sensor suchthat a replaceable collection media assembly inserted therein may beprevented from moving relative to the collection media assembly dockelement 200 in each of the x-direction, the y-direction, thez-direction, and the angular direction.

FIGS. 14A-15B illustrate various views of various sensor components ofan exemplary sensor in accordance with various embodiments describedherein. In particular, FIG. 14A and FIG. 14B illustrate variouscross-sectional views of an exemplary replaceable collection mediaassembly 100 disposed within a collection media assembly dock element200, wherein the replaceable collection media assembly 100 comprises animpactor nozzle 112. As described herein, the replaceable collectionmedia assembly 100 of a fluid composition sensor may be embodied as, forexample, a replaceable cassette comprising an upper cassette portion110, a lower cassette portion 120, and a particle collection slide 130.The upper cassette portion 110 and the lower cassette portion 120 maycollectively define a collection media housing configured secure theparticle collection slide 130 (e.g., the collection media) relative toeach of the two cassette portions 110, 120. As described herein, theupper cassette portion 110 may be configured to receive a volume offluid, for example, through an impactor nozzle 112 (e.g., via a nozzleinlet) positioned at a top portion thereof. The impactor nozzle 112 maybe configured to direct the volume of fluid toward a receiving area ofthe collection media disposed upon the particle collection slide 130 ina fluid flow direction at least substantially perpendicular to thecollection media. The volume of fluid may travel from the outlet 111 ofthe impactor nozzle 112 and pass across at least a portion of a surfacethe collection media 131 such that at least a portion of the pluralityof particles within the volume of fluid become disposed within thecollection media. As shown, upon passing over the particle collectionslide, the volume of fluid may continue to flow along a fluid flow paththrough one or more openings defined by the lower cassette portion 120located on either side of the particle collection slide 130.

As illustrated, the imaging device 300 of the fluid composition sensormay be operatively attached (e.g., via a printed circuit board) to thecollection media assembly dock element 200. The imaging device 300 maybe positioned directly adjacent and/or at least partially within animaging orifice extending through the collection media assembly dockelement 200 such that the imaging device 300 may have an unimpeded lineof sight to the particle collection slide 130. Such a configuration mayenable the imaging device 300 to capture an image of the plurality ofparticles embedded within a receiving area of the particle collectionslide 130 (e.g., the collection media) while the replaceable collectionmedia assembly 100 remains secured within the collection media assemblydock element 200. In various embodiments, a portion of the collectionmedia assembly dock element 200 (e.g., the bottom alignment protrusion211) may extend upward into an interior cavity of a replaceablecollection media assembly 100 secured thereto. For example, thecollection media assembly dock element 200 may be configured such thatat least a portion of the imaging device 300 secured thereto may bedisposed within in the interior cavity of the replaceable collectionmedia assembly 100.

In various embodiments, at least a portion of the collection mediaassembly dock element 200 may engage one or more of a bottom surface, asidewall, and a geometric feature of the replaceable collection mediaassembly 100 in order to stabilize the position of the replaceablecollection media assembly 100 relative to the collection media assemblydock element 200 and/or the imaging device 300 attached thereto. Forexample, the replaceable collection media 100 may be secured within thecollection media assembly dock element 200 such that the particlecollection slide 130 is arranged within the fluid composition sensor atan internal particle imaging distance 125 away from the imaging device300. The internal particle imaging distance 125 may be such that thereceiving area of a collection media disposed upon the particlecollection slide may be located within the field of view of the imagingdevice 300. For example, in various embodiments, the internal particleimaging distance may be at least approximately between about 100 micronsand about 5 mm (e.g., 1 mm). As described herein, the internal particleimaging distance 125 may be selectively designated in order to optimizethe imaging capability of the imaging device 300 with respect to theplurality of particles embedded within the collection media, so as tofacilitate the particle analysis function of the fluid compositionsensor.

As illustrated, the particle collection slide 130 may be configured toreceive a plurality of particles from an exemplary volume of fluiddispensed from the outlet of the impactor nozzle 112 (e.g., the fluidinlet 111) at a receiving area of the collection media disposed thereon.As described herein, the receiving area of the collection media maycorrespond to the configuration of the outlet of the impactor nozzle 112from which the exemplary volume of fluid is dispensed prior to impactingthe collection media. For example, the receiving area of the collectionmedia may be defined at least in part by an outer perimeter with a shapecorresponding to that of the outlet of the impactor nozzle 112. Further,in various embodiments, the size of the receiving area and/or thepercentage of particles within the volume of fluid that impact thecollection media may correspond at least in part to the interiorparticle imaging distance 115, defined by the distance between theoutlet of the impactor nozzle and the collection media. In variousembodiments, the internal particle collection distance 115 may beconfigured so as to maximize the percentage of particles from volume offluid that become embedded within the collection media. The internalparticle collection distance 115 may be set such that the entirety ofthe receiving area of the collection media disposed upon the particlecollection slide 130 may be located within the field of view of theimaging device 300. As described herein, the internal particlecollection distance 115 may be selectively designated in order tooptimize the particle collection function of the fluid compositionsensor. In various embodiments, the fluid composition sensor 10 may beconfigured to facilitate the convergence of the field of view of theimaging device 300 and the receiving area of the collection media. Forexample, in various embodiments, a central axis of the impactor nozzle112 (e.g., a fluid inlet 111) may be at least substantially aligned withthe field of view of the imaging device 300. Further, the outlet of theimpactor nozzle 112 may be configured so as to comprise a shape that isat least substantially similar to the field of view of the imagingdevice 300. For example, in an exemplary circumstance wherein the fieldof view is defined by an aspect ratio of 3:4, the outlet of the impactornozzle 112 may comprise a rectangular cross-section with aheight-to-width ratio of 3:4, and having an overall size correspondingto the configuration of the imaging device 300.

FIGS. 15A and 15B illustrate various side sectional views of anexemplary replaceable collection media assembly 100 disposed within acollection media assembly dock element 200, wherein the replaceablecollection media assembly 100 does not comprise an impactor nozzle 112.In such a configuration, the fluid inlet 111 of the replaceablecollection media assembly 110 may be defined by an upper cassetteportion 110. As illustrated, the fluid inlet 111 of the replaceablecollection media assembly 100 may be configured to receive a samplevolume of fluid from an outlet of the impactor nozzle, which may beembodied as a distinct component of the sensor or may be attached to oneof the other components defining at least a portion of the fluid flowpath 90 within the sensor. For example, the upper cassette portion maycomprise an impactor nozzle alignment element 116 configured to engagethe outlet of the impactor nozzle 112 so as to minimize the risk of aportion of the volume of air being lost between the impactor nozzle 112and the fluid inlet 111.

The fluid inlet 111 may be configured such that the volume of fluidpasses therethrough in a fluid flow direction at least substantiallyperpendicular to the collection media. As described herein, the volumeof fluid may travel from the fluid inlet 111 and pass across at least aportion of a surface the collection media disposed upon the particlecollection slide 130 such that at least a portion of the plurality ofparticles within the volume of fluid become disposed within thecollection media. Upon passing over the particle collection slide 130,the volume of fluid may continue to flow along a fluid flow path 90through one or more openings defined by the lower cassette portion 120located on either side of the particle collection slide 130.

As illustrated, the particle collection slide 130 may be configured toreceive a plurality of particles from an exemplary volume of fluiddispensed from the fluid inlet 111 at a receiving area of the collectionmedia disposed thereon. As described herein, the receiving area of thecollection media may correspond to the configuration of the fluid inlet111 from which the exemplary volume of fluid is dispensed prior toimpacting the collection media. For example, the receiving area of thecollection media may be defined at least in part by an outer perimeterwith a shape corresponding to that of the fluid inlet 111. Further, invarious embodiments, the size of the receiving area and/or thepercentage of particles within the volume of fluid that impact thecollection media may correspond at least in part to the interiorparticle imaging distance 115, defined by the distance between the fluidinlet 111 and the collection media. In various embodiments, the internalparticle collection distance 115, as described herein, may be configuredso as to maximize the percentage of particles from volume of fluid thatbecome embedded within the collection media. As described above, thefluid composition sensor may be configured to facilitate the convergenceof the field of view of the imaging device 300 and the receiving area ofthe collection media. For example, in various embodiments, a centralaxis of the fluid inlet 111 may be at least substantially aligned withthe field of view of the imaging device 300. Further, the fluid inlet111 may be configured so as to comprise a shape that is at leastsubstantially similar to the field of view of the imaging device 300.For example, in an exemplary circumstance wherein the field of view isdefined by an aspect ratio of 3:4, the fluid inlet 111 may comprise arectangular cross-section with a height-to-width ratio of 3:4,corresponding to the configuration of the imaging device 300.

FIG. 16 illustrates a perspective view of an exemplary replaceablecollection media assembly in accordance with various embodimentsdescribed herein. In particular, FIG. 16 illustrates a replaceablecollection media assembly 400, wherein the replaceable collection mediaassembly 400 is embodied as a disposable slide. In various embodiments,the disposable slide 400 may comprise a transparent substrate 132 havinga collection media 131 on at least a portion of an upper surfacethereof. As described herein, the collection media 131 may be configuredto receive one or more particles of a plurality of particles viainteraction with a volume of fluid traveling through a fluid compositionsensor along a fluid flow path. In various embodiments, the disposableslide may further comprise a slide frame element 402 configured tosupport the transparent substrate 132 and the collection media 131attached thereto. In various embodiments, at least a portion of theslide frame element 402 may be embodied as a handle configured tofacilitate user interaction with the disposable slide so as to enablethe removal and/or replacement of the collection media 131 from thefluid composition sensor 10. In various embodiments, the disposableslide may comprise at least two distinct and separable components. Forexample, in various embodiments the slide frame element 402 may beselectively detachable from the transparent substrate 132.

In various embodiments, the disposable slide may further comprise one ormore compression elements 401. For example, the one or more compressionelements 401 may comprise protrusions extending from the slide frameelement that are configured to engage a portion of the fluid compositionsensor upon the disposable slide 400 being inserted into the internalsensor portion of the sensor, as described herein. In variousembodiments, upon being inserted into the internal sensor portion of thesensor, the one or more compression elements 401 may be embodied as, forexample, springs molded into the slide frame element 402 that areconfigured so as to apply a pressing force against at least an adjacentportion of the sensor. Alternatively, or additionally, the one or morecompression elements may comprise protrusions and/or surfaces disposedabout the disposable slide 400 that may be configured to receive acompression force from a corresponding spring element disposed withinthe fluid composition sensor. The one or more compression elements 401may facilitate the stabilization of the disposable handle 400 within aninternal sensor portion of the fluid composition sensor by constrainingthe movement of the disposable slide 400 in a vertical direction. Invarious embodiments, the disposable slide 400 may further comprise alatch. For example, in various embodiments, the latch may be defined byone of the compression elements. The latch may be configured to, uponthe insertion of the disposable slide 400 into the fluid compositionsensor, engage an adjacent interior portion of the sensor so as toprevent the disposable slide 400 from being removed from the sensor. Thelatch may be configured such that, upon being pulled by a user in aremoval direction, the latch may engage the adjacent internal sensorportion so as to constrain further movement of the disposable slide 400relative to the fluid composition sensor in the removal direction.

In various embodiments, the disposable slide 400 may further compriseone or more identification elements configured to uniquely identify theparticular disposable slide 400 corresponding thereto. Theidentification element 403 may comprise, for example, a bar code, QRcode, serial number, and/or the like. In various embodiments, theidentification element 403 may be disposed upon and/or within thetransparent substrate 132 of the disposable slide 400. In such aconfiguration, the identification element 403 may be positioned aboutthe disposable slide 400 such that the identification element 403 may becaptured and/or identified by an imaging device disposed either withinor external to the fluid composition sensor, as described herein.Further, in various embodiments, a controller of the fluid compositionsensor, as described herein, may be used in combination with theaforementioned imaging device to facilitate the identification and/orprocessing of the disposable slide 400 based at least in part on theidentification element 403.

FIG. 17 illustrates a cross-sectional view of an exemplary fluidcomposition according to various embodiments described herein. Inparticular, FIG. 17 illustrates an exemplary replaceable collectionmedia assembly 100 disposed within a fluid composition sensor, whereinthe replaceable collection media assembly 100 is embodied as adisposable slide 400. As described herein, the fluid composition sensormay be configured to receive a disposable slide 400 having a collectionmedia 131 attached thereto through an opening in the sensor housing. Thefluid composition sensor may position the slide 400 at least partiallywithin an internal sensor portion, such that the collection media 131 isdisposed within a fluid flow path defined by a sample volume of fluidtraveling through the sensor. Disposable slide 400 may be arrangedwithin the fluid composition sensor such that at least a portion of thecollection media 131 disposed upon the transparent substrate 132 may beat least substantially aligned with both an outlet 111 of the impactornozzle 112 and an imaging device 300, as described herein. In such aconfiguration, the collection media 131 may define a receiving areaconfigured to receive a plurality of particles from the sample volume offluid. For example, the receiving area of the collection media 131 maybe positioned within the field of view of the imaging device 300.

As illustrated, the fluid composition sensor may be configured such thatwhen the disposable slide 400 is positioned within the internal portionof the sensor in a particle collection position, the compressionelements 401 of the disposable slide 400 may engage a correspondingadjacent portion of one or more sensor components disposed within thesensor. For example, the compression elements 401 may be predisposed toapply an at least substantially vertical pressing force to thecorresponding adjacent sensor portion such that the disposable slide 400may receive a reciprocal force from the adjacent sensor portion. Invarious embodiments, the reciprocal forces realized by the disposableslide 400 in the opposite vertical direction may be such that the slide400 may be pressed against one or more vertically constrained surfaceswithin the sensor. As such, the reciprocal forces exerted on thedisposable slide 400—and provoked by the one or more compressionelements 401—may function to stabilize the disposable slide 400 withinthe sensor in the vertical direction. As illustrated, for example, thereciprocal forces acting on the disposable slide 400 may cause at leasta portion of the slide 400, such as, for example, a portion of thetransparent substrate 132 at least substantially adjacent the receivingarea of the collection media 131, to be pressed against the imagingdevice 300 and/or a protective housing having the imaging device 300disposed therein. In such a configuration, the engagement of the slide400 to the imaging device 300 may create a seal along the interfacebetween the slide 400 and the imaging device 300 that may function toprotect the imaging device 300 from contamination, as described herein.Further, the securing of the slide relative to the imaging device 300may enable the fluid composition sensor to control the internal particleimaging distance between the imaging device 300 and the transparentsubstrate, so as to optimize the imaging capability of the imagingdevice 300 with respect to the plurality of particles embedded withinthe collection media 131. Similarly, the slide 400 relative to theimaging device 300 may enable the fluid composition sensor to controlthe internal particle collection distance 115 between the collectionmedia 131 and the outlet of the impactor nozzle 112, so as to optimizethe particle collection functionality of the sensor, as describedherein.

In various embodiments, the fluid composition sensor may furthercomprise a slide ejection button 410 configured to facilitate theremoval of the disposable slide 400 from the housing of the sensor. Asdescribed herein, the latch 411 of the disposable slide 400 may beconfigured to engage the slide ejection button 410 so as to prevent thedisposable slide 400 from being removed from the sensor. As illustrated,the latch 411 is defined by one of the compression elements 401. Thelatch 411 may be configured such that, upon being pulled by a user in aremoval direction (e.g., a substantially horizontal direction), thelatch 411 may engage the slide ejector button 410 so as to prevent thedisposable slide 400 from further moving relative to the fluidcomposition sensor in the removal direction. For example, wherein thelatch 411 is defined by one of the compression elements 401, the latch411 may engage the slide ejection button 410 in a substantiallydifferent direction (e.g., the x-direction) than the direction of theaforementioned compression force configured to at least partially securethe slide 400 in a vertical direction (e.g., the y-direction). The fluidcomposition sensor may be configured such that, upon receiving userinput (e.g., a pushing force) at the slide ejection button 410, aportion of the slide ejection button 410 may move within the sensorcausing the latch 411 to become disengaged therewith, thereby enablingthe movement of the disposable slide 400 relative to the fluidcomposition sensor in the removal direction. Further, in variousembodiments, the fluid composition may further comprise an ejectionspring configured to apply a pushing force against the disposable slide400 in the removal direction when the slide is fully positioned in theparticle collection position, as described above. In the exemplarycircumstance wherein a latch 411 of the slide 400 becomes disengagedwith an adjacent portion of the slide ejector button 410, the ejectionspring 412 may press against the slide 400 so as to at least partiallyremove the slide 400 from the internal portion of the sensor.

Controller

As shown in FIG. 18, the fluid composition sensor 10 may comprise acontroller 50 configured to control the various operations associatedwith the particle collection function of a fluid composition sensor 10,as well as the imaging and analysis of the particles collected by thesensor to determine at least one particle characteristic of a volume offluid received by sensor 10. As illustrated in FIG. 18, the controller50 may comprise a memory 51, a processor 52, input/output circuitry 53,communication circuitry 55, an imaging device data repository 107, acollection media characteristic database 54, particle imaging circuitry56, particle type identification circuitry 57, and particle collectioncircuitry 58. The controller 50 may be configured to execute theoperations described herein. Although the components are described withrespect to functional limitations, it should be understood that theparticular implementations necessarily include the use of particularhardware. It should also be understood that certain of the componentsdescribed herein may include similar or common hardware. For example,two sets of circuitry may both leverage use of the same processor,network interface, storage medium, or the like to perform theirassociated functions, such that duplicate hardware is not required foreach set of circuitry. The use of the term “circuitry” as used hereinwith respect to components of the controller 50 should therefore beunderstood to include particular hardware configured to perform thefunctions associated with the particular circuitry as described herein.

The term “circuitry” should be understood broadly to include hardwareand, in some embodiments, software for configuring the hardware. Forexample, in some embodiments, “circuitry” may include processingcircuitry, storage media, network interfaces, input/output devices, andthe like. In some embodiments, other elements of the controller 50 mayprovide or supplement the functionality of particular circuitry. Forexample, the processor 52 may provide processing functionality, thememory 51 may provide storage functionality, the communicationscircuitry 55 may provide network interface functionality, and the like.

In some embodiments, the processor 52 (and/or co-processor or any otherprocessing circuitry assisting or otherwise associated with theprocessor) may be in communication with the memory 51 via a bus forpassing information among components of the apparatus. The memory 51 maybe non-transitory and may include, for example, one or more volatileand/or non-volatile memories. For example, the memory 51 may be anelectronic storage device (e.g., a computer readable storage medium). Invarious embodiments, the memory 51 may be configured to storeinformation, data, content, applications, instructions, or the like, forenabling the apparatus to carry out various functions in accordance withexample embodiments of the present disclosure. It will be understoodthat the memory 51 may be configured to store partially or wholly anyelectronic information, data, data structures, embodiments, examples,figures, processes, operations, techniques, algorithms, instructions,systems, apparatuses, methods, look-up tables, or computer programproducts described herein, or any combination thereof. As a non-limitingexample, the memory 51 may be configured to store particle size data,particle type data, particle impaction depth data, particle image data,particle shape data, particle cross-sectional area data, particle massdata, particle density data, and particulate matter mass concentrationdata associated with a volume of fluid. In various embodiments, thememory may be further configured to store one or more particle impactiondepth-momentum look-up tables.

The processor 52 may be embodied in a number of different ways and may,for example, include one or more processing devices configured toperform independently. Additionally or alternatively, the processor mayinclude one or more processors configured in tandem via a bus to enableindependent execution of instructions, pipelining, and/ormultithreading. The use of the term “processing circuitry” may beunderstood to include a single core processor, a multi-core processor,multiple processors internal to the apparatus, and/or remote or “cloud”processors.

In an example embodiment, the processor 52 may be configured to executeinstructions stored in the memory 51 or otherwise accessible to theprocessor. Alternatively, or additionally, the processor may beconfigured to execute hard-coded functionality. As such, whetherconfigured by hardware or software methods, or by a combination thereof,the processor may represent an entity (e.g., physically embodied incircuitry) capable of performing operations according to an embodimentof the present disclosure while configured accordingly. Alternatively,as another example, when the processor is embodied as an executor ofsoftware instructions, the instructions may specifically configure theprocessor to perform the algorithms and/or operations described hereinwhen the instructions are executed.

In some embodiments, the controller 50 may include input-outputcircuitry 53 that may, in turn, be in communication with the processor52 to provide output to the user and, in some embodiments, to receiveinput such as a command provided by the user. The input-output circuitry53 may comprise a user interface, such as a graphical user interface(GUI), and may include a display that may include a web user interface,a GUI application, a mobile application, a client device, or any othersuitable hardware or software. In some embodiments, the input-outputcircuitry 53 may also include a display device, a display screen, userinput elements, such as a touch screen, touch areas, soft keys, akeyboard, a mouse, a microphone, a speaker (e.g., a buzzer), a lightemitting device (e.g., a red light emitting diode (LED), a green LED, ablue LED, a white LED, an infrared (IR) LED, an ultraviolet (UV) LED, ora combination thereof), or other input-output mechanisms. The processor52, input-output circuitry 53 (which may utilize the processingcircuitry), or both may be configured to control one or more functionsof one or more user interface elements through computer-executableprogram code instructions (e.g., software, firmware) stored in anon-transitory computer-readable storage medium (e.g., memory 51).Input-output circuitry 53 is optional and, in some embodiments, thecontroller 50 may not include input-output circuitry. For example, wherethe controller 50 does not interact directly with the user, thecontroller 50 may generate user interface data for display by one ormore other devices with which one or more users directly interact andtransmit the generated user interface data to one or more of thosedevices. For example, the controller 50, using user interface circuitrymay generate user interface data for display by one or more displaydevices and transmit the generated user interface data to those displaydevices.

The communications circuitry 55 may be a device or circuitry embodied ineither hardware or a combination of hardware and software that isconfigured to receive and/or transmit data from/to a network and/or anyother device, circuitry, or module in communication with the controller50. For example, the communications circuitry 55 may be configured tocommunicate with one or more computing devices via wired (e.g., USB) orwireless (e.g., Bluetooth, Wi-Fi, cellular, and/or the like)communication protocols.

In various embodiments, the processor 52 may be configured tocommunicate with the particle imaging circuitry 56. The particle imagingcircuitry 56 may be a device or circuitry embodied in either hardware ora combination of hardware and software that is configured to receive,process, generate, and/or transmit data, such as an image captured bythe imaging device 300. In various embodiments, the particle imagingcircuitry 56 may be configured to analyze one or more images captured bythe imaging device 300 of the fluid composition sensor 10 to determinewhich particles of the plurality of particles present within thecollection media 131 were newly received by the collection media 131during a recent particle analysis. The particle imaging circuitry 56 mayreceive from the imaging device a first captured particle image and asecond captured particle image, captured at a first time and a secondtime, respectively, wherein the first time represents the start of ananalysis of the one or more particles of the plurality of particlescaptured by the collection media 131 by the fluid composition sensor 10and the second time is subsequent the first time (occurs after the firsttime). In such a configuration, the device may be configured todistinguish between particles present within the collection media 131 atthe start of the particle analysis and particles that were newlyreceived by the collection media 131 by comparing the respectiveparticle images captured at the first and second times and identifyingany particles from the second captured particle image that were notcaptured in the first captured particle image. In various embodiments,the particle imaging circuitry 56 may be further configured to analyzeone or more images captured by the imaging device 300 of the fluidcomposition sensor 10 to determine the size of each of the one or moreparticles of the plurality of particles within the collection media 131.In various embodiments, the size of a particle may be defined by thecross-sectional area of the particle. In various embodiments, theparticle imaging circuitry 56 may be configured to determine theparticle size of particles with any of a variety of particle sizes. Asan example, the particle imaging circuitry 56 may be configured todetermine particle sizes of particles having a diameter of between about0.3 and about 100 microns (e.g., 2.5 microns), and thus, a size categorywith which the particle may be associated, such as, for example, PM10,PM4, PM2.5, or PM1. In various embodiments, the controller and/or theparticle imaging circuitry 56 may be further configured to analyze oneor more images captured by the imaging device 300 of the fluidcomposition sensor 10 to determine the shape of each of the one or moreparticles of the plurality of particles within the collection media 131.In various embodiments, a particle shape may be defined at least in partby a particle cross-sectional area. The particle imaging circuitry 56may be further configured to determine the particle impaction depth ofeach of the one or more particles of the plurality of particles withinthe collection media 131 using one or more image focusing techniques.The particle imaging circuitry 56 may be configured to executeinstructions stored, for example, in the memory 51 for carrying out theone or more image focusing techniques. In various embodiments, the oneor more image focusing techniques may comprise one or computationaltechniques, such as, for example, Angular Spectrum Propagation (ASP). Inother embodiments, opto-mechanical adjustment may be used as an imagefocusing technique. In various embodiments, the particle imagingcircuitry 56 may use the one or more image focusing techniques todetermine a depth of focus 122 for each of the one or more particles ofthe plurality of particles within the collection media. Upon determininga depth of focus for each of the one or more particles, the particleimaging circuitry 56 may be configured to calculate, using knowndimensions of the fluid composition sensor 10 such as, for example, thecollection media thickness and the distance between the transparentsubstrate 108 and the imaging device 300, the impaction depth 121 ofeach of the one or more particles of the plurality of particles withinthe collection media 131. In various embodiments, for example, theimpaction depth 121 of a particle within the collection media 131 may becalculated by subtracting the measured depth of focus 122 of a particlefrom the sum of the collection media thickness, the transparentsubstrate thickness, and the distance between the transparent substrate108 and the imaging device 300. The particle imaging circuitry 56 maysend and/or receive data from the imaging device data repository 107. Invarious embodiments, the particle imaging circuitry 56 may be configuredto determine one or more particle characteristics of a particle usingone or more machine learning techniques. In various embodiments, the oneor more machine learning techniques used by the particle imagingcircuitry 56 to determine the one or more particle characteristics ofthe particle may comprise using deep supervised learning with one ormore labeled datasets of one or more known particle characteristics,such as, for example, particle type, particle velocity, particle size,particle shape, and/or any other data generated, transmitted, and/orreceived by the controller 50.

In various embodiments, the processor 52 may be configured tocommunicate with the particle type identification circuitry 57. Theparticle type identification circuitry 57 may be a device or circuitryembodied in either hardware or a combination of hardware and softwarethat is configured to identify a particle type and/or particle speciesof one or more particles of the plurality of particles received by thecollection media 131. In various embodiments, a plurality of particleswithin a volume of fluid may comprise one or more particles of variousparticle types, such as, for example, one or more of bacteria, pollen,spores, molds, biological particles, soot, inorganic particles, andorganic particles. In various embodiments, the particle typeidentification circuitry 57 may determine the particle type and/orparticle species of each of the one or more particles of the pluralityof particles received by the collection media 131 using one or moremachine learning techniques. In various embodiments, the one or moremachine learning techniques used by the particle type identificationcircuitry 57 to determine the particle type and/or species of each ofthe one or more particles of the plurality of particles may compriseanalyzing an image captured by the imaging device 300, particle sizedata, particle shape data, and/or any other data generated, transmitted,and/or received by the controller 50. In various embodiments, theparticle type identification circuitry 57 may send and/or receive datafrom the imaging device data repository 107. In various embodiments, theparticle type identification circuitry 57 may be configured to comparethe determined particle initial velocity for a particle to the particlevelocity approximated based at least in part on a known flow rate offluid moving through the fluid composition sensor 10 and generatevelocity comparison data associated with the particle. In variousembodiments, the particle type identification circuitry 57 may beconfigured to execute a feedback loop, wherein one or more velocitycomparison data associated with one or more particles of the pluralityof particles received by the collection media 131 may define one or moreinputs into a machine learning model in order to increase a rate ofmachine learning associated with the one or more machine learningtechniques, as described herein.

In various embodiments, the fluid composition sensor 10 may beconfigured with, or in communication with, a collection mediacharacteristic database 54. The collection media characteristic database54 may be stored, at least partially on the memory 51 of the system. Insome embodiments, the collection media characteristic database 54 may beremote from, but in connection with, the fluid composition sensor 10.The collection media characteristic database 54 may contain information,such as one or more particle impaction depth-momentum relationshiplook-up tables. In various embodiments, a particle impactiondepth-momentum relationship look-up table may comprise a data matrixused to define a relationship between a particle impaction depth and aparticle initial momentum (i.e. the momentum of a particle at areceiving surface of the collection media 131, wherein the particle isreceived by the collection media 131 at the receiving surface, asdescribed herein) for a particular collection media type. Variousparticle impaction depth-momentum relationship look-up tables maycomprise data matrices used to define a relationship between a particleimpaction depth and a particle initial momentum for various collectionmedia types.

The particle collection circuitry 58 may be a device or circuitryembodied in either hardware or a combination of hardware and softwarethat is configured to control the particle collection functionality ofthe fluid composition sensor 10, as described herein. For example, theparticle collection circuitry 58 may control a fan disposed within thefluid control sensor 10 in order to execute a fluid sample collectionprocess by pulling a volume of fluid from an ambient environment intoand through the fluid composition sensor 10. In various embodiments, theparticle collection circuitry 58 may configure the fluid compositionsensor between an open configuration and a closed configuration, asdescribed herein. In various embodiments, the particle collectioncircuitry 58 may be configured to lock the fluid composition sensor 10in a closed configuration during the fluid sample collection process.Further, the particle collection circuitry 58 may be configured todetermine when the collection of the fluid sample is complete (e.g.,after a predetermined amount of time, after a number of particlespresent within the collection media has surpassed a predeterminedthreshold number of particles, and/or after a percentage of particlecoverage within a field of view has surpassed threshold particlecoverage percentage). Upon such a determination, the particle collectioncircuitry 58 may be configured to selectively unlock the fluidcomposition sensor 10 and configure the sensor 10 in an openconfiguration. Further, in various embodiments, the particle collectioncircuitry 58 may facilitate the automated reconfiguration and/orreplacement of one or more collection media assemblies, as describedherein. In various embodiments, the particle collection circuitry 58 maycommunicate with the particle imaging circuitry 56 in order tofacilitate the capturing of an image of an identification elementdisposed upon a replaceable collection media assembly and subsequentidentification thereof. In various embodiments, the image of theidentification element disposed upon the replaceable collection mediaassembly may be communicated to one or more components (e.g., internalsensor components and/or external system databases) to facilitate theidentification of the particular replaceable collection media assembly100 captured in the image.

In various embodiments, the fluid composition sensor 10 may beconfigured with, or in communication with, an imaging device datarepository 107. The imaging device data repository 107 may be stored, atleast partially on the memory 51 of the system. In some embodiments, theimaging device data repository 107 may be remote from, but in connectionwith, the fluid composition sensor 10. The imaging device datarepository 107 may contain information, such as images relating to oneor more potential components of fluids. In some embodiments, the imagingdevice data repository 107, and/or other similar reference databases incommunication with the fluid composition sensor 10, may comprisenon-image information used to identify particles (e.g., for florescentparticles, a spectrometer may be used by the fluid composition sensor 10as discussed herein and the fluid composition sensor 10 may receivespectrum information to identify and/or classify the particles). In someembodiments, the fluid composition sensor 10 may also use machinelearning for identifying and/or classifying particles, such that thefluid composition sensor 10 may use a reference database, such as theimaging device data repository 107, to initially train the fluidcomposition sensor 10 and then may be configured to identify and/orclassify particles without referencing the imaging device datarepository 107 or other reference databases (e.g., a system may not bein active communication with the imaging device data repository 107during regular operations).

CONCLUSION

Many modifications and other embodiments will come to mind to oneskilled in the art to which this disclosure pertains having the benefitof the teachings presented in the foregoing descriptions and theassociated drawings. Therefore, it is to be understood that thedisclosure is not to be limited to the specific embodiments disclosedand that modifications and other embodiments are intended to be includedwithin the scope of the appended claims. Although specific terms areemployed herein, they are used in a generic and descriptive sense onlyand not for purposes of limitation.

That which is claimed:
 1. A device for detecting fluid particlecharacteristics comprising: a fluid composition sensor configured toreceive a volume of fluid, the fluid composition sensor comprising: aremovable fluid flow component disposed within an internal sensorportion and configured to define at least a portion of a fluid flowpath; a collection media assembly dock element configured to receive areplaceable collection media assembly comprising a collection mediaconfigured to receive one or more particles of a plurality of particleswithin the volume of fluid such that the replaceable collection mediaassembly is arranged within the internal sensor portion in a particlecollection position; a housing defining the internal sensor portion andbeing selectively configurable between an open housing configuration anda closed housing configuration, wherein when the housing is in theclosed housing configuration, a vertical compression force is applied tothe replaceable collection media assembly so as to at least partiallyconstrain the replaceable collection media assembly in a verticaldirection; an imaging device configured to capture an image of at leasta portion of the one or more particles of the plurality of particlesreceived by the collection media; a controller configured to determine,based at least in part on the image, at least one particlecharacteristic of the plurality of particles of the volume of fluid;wherein at least a portion of the fluid flow path extends in a fluidflow direction that is at least substantially toward the collectionmedia; wherein the collection media assembly dock element is configuredto constrain relative movement between the replaceable collection mediaassembly and the imaging device in a lateral direction.
 2. The device ofclaim 1, wherein the imaging device is configured to capture the imageof the at least a portion of the one or more particles of the pluralityof particles received by the collection media using lensless holography.3. The device of claim 1, wherein the collection media assembly dockelement comprises one or more alignment features configured to engagethe replaceable collection media assembly so as to constrain thereplaceable collection media assembly against movement relative to thecollection media assembly dock element.
 4. The device of claim 3,wherein the replaceable collection media assembly further comprises oneor more alignment features configured to engage the collection mediaassembly dock element so as to constrain the replaceable collectionmedia assembly against movement relative to the collection mediaassembly dock element in at least a second direction.
 5. The device ofclaim 3, wherein the housing comprises a fluid inlet configured toreceive the volume of fluid; wherein the open housing configurationprovides an opening through which the replaceable collection mediaassembly may be removed from within the internal sensor portion, andwherein the fluid composition sensor in the closed configuration isconfigured to constrain the replaceable collection media assemblyagainst movement relative to the collection media assembly dock elementin at least the lateral direction, a vertical direction, and an angulardirection.
 6. The device of claim 5, wherein the removable fluid flowcomponent is configured to be removable from within the internal sensorportion when the fluid composition sensor in the open configuration. 7.The device of claim 6, wherein the removable fluid flow componentcomprises a first fluid flow component part and a second fluid flowcomponent part, wherein the first fluid flow component part isconfigured to be separable from the second fluid flow component part tofacilitate selective access to an internal portion of the removablefluid flow component.
 8. The device of claim 1, wherein the collectionmedia assembly dock element comprises an imaging orifice configured soas to define a line of sight to the one or more particles received bythe collection media, the line of sight extending through at least aportion of the collection media assembly dock element.
 9. The device ofclaim 8, further comprising a removable transparent protective coverarranged within the internal sensor portion and configured to cover atleast a portion of the imaging orifice.
 10. The device of claim 1,wherein the imaging device is operatively secured to the collectionmedia assembly dock element.
 11. The device of claim 1, wherein thefluid flow path is defined at least in part by a fluid impaction outletdisposed within the internal sensor portion and configured relative tothe collection media assembly dock element so as to direct the volume offluid in the fluid flow direction at least substantially perpendicularto the collection media of the replaceable collection media assemblyreceived by the collection media assembly dock element.
 12. The deviceof claim 11, wherein the fluid impaction outlet is defined at least inpart by a fluid impaction outlet shape that is at least substantiallysimilar to a field of view shape of the imaging device.
 13. The deviceof claim 12, wherein the fluid impaction outlet is defined at least inpart by a fluid impaction outlet area that is at least substantiallysimilar to a field of view area of the imaging device disposed.
 14. Thedevice of claim 11, wherein the fluid composition sensor is configuredsuch that at least a portion of the collection media of the replaceablecollection media assembly received by the collection media assembly dockelement is at least substantially aligned with a field of view of theimaging device and a central axis of the fluid impaction outlet.
 15. Thedevice of claim 11, wherein the wherein the fluid flow path is definedat least in part by an impactor nozzle, and wherein the fluid impactionoutlet is defined by an impactor nozzle outlet of the impactor nozzle.16. The device of claim 1, further comprising at least one illuminationsource configured to emit one or more light beams so as to engage thecollection media of the replaceable collection media assembly receivedby the collection media assembly dock element and illuminate the one ormore particles received by the collection media.
 17. The device of claim1, wherein the fluid composition sensor is configured such that thevolume of fluid passes over at least a portion of an internal circuitrydisposed within the internal sensor portion before the volume of fluidis dispensed from the internal sensor portion through a fluid outlet ofthe fluid composition sensor.
 18. The device of claim 1, wherein one orboth of the controller and the imaging device is configured to read oneor more identification elements disposed on the replaceable collectionmedia assembly received by the collection media assembly dock element soas to identify the replaceable collection media assembly, wherein theone or more identification elements configured to uniquely identify thereplaceable collection media assembly.
 19. The device of claim 1,wherein the fluid composition sensor is configured to consecutivelyreceive a plurality of replaceable collection media assemblies withinthe internal sensor portion in series.
 20. A method for detecting fluidparticle characteristics comprising: receiving, via a fluid compositionsensor, a volume of fluid; directing the volume of fluid, via animpactor nozzle, toward a collection media of a replaceable collectionmedia assembly; receiving, via the collection media, one or moreparticles of a plurality of particles within the volume of fluid;capturing, using an imaging device disposed within the fluid compositionsensor, an image of the one or more particles of the plurality ofparticles received by the collection media; determining, based at leastin part on the image, at least one particle characteristic of theplurality of particles of volume of fluid; upon determining the at leastone particle characteristic of the plurality of particles of volume offluid, reconfiguring the fluid composition sensor to an openconfiguration; and replacing the replaceable collection media assemblywith a second replaceable collection media assembly; wherein the secondreplaceable collection media assembly comprises at least one alignmentfeature, and wherein replacing the replaceable collection media assemblywith the second replaceable collection media assembly comprisespositioning the second replaceable collection media assembly within aportion of the sensor based at least in part on the at least onealignment feature; wherein when the fluid composition sensor is in aclosed configuration, a vertical compression force is applied to thereplaceable collection media assembly so as to at least partiallyconstrain the replaceable collection media assembly in a verticaldirection.
 21. The method of claim 20, wherein reconfiguring the sensorto the closed configuration comprises constraining the secondreplaceable collection media assembly in at least a lateral direction,the vertical direction, and an angular direction relative to the sensor.22. The method of claim 21, wherein the image of the one or moreparticles of the plurality of particles received by the collection mediais captured using lensless holography.